Explosive Device Reconstruction through Chemical and Trace Evidence Analysis: A Homicide Case Investigation

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This study reports on a homicide case in which a homemade explosive (HME) device was used, focusing on the systematic recovery and chemical analysis of trace evidence from highly degraded exhibits collected five months after the incident. Case presentation This study presents a homicide case in which a homemade explosive (HME) device was deployed in an agricultural field, resulting in the death of a single victim. The suspects allegedly used bombs containing fragmentary materials. Evidence, including soil, debris, metallic fragments, jute thread, stone chips, the victim’s clothing, and burned skin, was recovered five months after the incident under degraded conditions. Sequential solvent extractions (ether, acetone, water, sodium hydroxide, and pyridine) were performed, followed by chemical tests, Thin Layer Chromatography (TLC), and Fourier Transform Infrared Spectroscopy (FTIR). Analytical results confirmed the presence of low explosive constituents—potassium nitrate, ammonium nitrate, metallic aluminium, and elemental sulphur—in multiple exhibits. No high explosives or diesel fuel were detected. Physical evidence supported the use of a fragmentation-oriented IED, designed to increase lethality through shrapnel dispersal. Despite significant sample decomposition, maggot infestation, and thermal alteration, the adopted protocols enabled the reliable detection of explosive residues, aiding in the reconstruction of the device and corroborating witness statements. Conclusion This investigation demonstrated the effectiveness of integrated chemical analysis and trace evidence examination in post-blast homicide cases, even with heavily degraded samples and delayed submission. The combination of sequential extraction methods and multi-technique instrumental analysis provided robust and probative findings, confirming the use of nitrate-based HME with added fragmentation materials. This case highlights the importance of meticulous evidence collection, comprehensive analytical approaches, and adaptability of forensic protocols to challenging post-blast scenarios, thereby enhancing investigative and prosecutorial outcomes in explosive-related crimes. Post-Blast analysis Homemade IED Homicide investigation Explosive residues Forensic Trace evidence Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction Explosive-related homicides are among the most complex cases in forensic science, largely because of the destructive nature of blast events and the consequent fragmentation and dispersion of physical evidence. Post-blast environments often contain commingled debris, vaporized or thermally altered residues, and trace particulates that may be present in minute quantities and subject to rapid environmental degradation [ 13 , 18 ]. The recovery, preservation, and accurate analysis of these traces are critical for reconstructing the sequence of events, determining the type and origin of the explosive used, and establishing evidentiary links between the device, the scene, and potential suspects [ 15 ]. Achieving this requires a multidisciplinary approach, combining systematic scene processing, chemical characterization, and trace evidence examination [ 16 ]. Recent advances in analytical techniques, including Thin Layer Chromatography (TLC), Fourier Transform Infrared Spectroscopy (FTIR), and other spectrometric and chromatographic methods, have significantly enhanced the detection sensitivity and specificity for explosive residues, even in complex post-blast matrices [ 14 , 17 ]. This study applies such a combined forensic methodology to a fatal case involving a Homemade Explosives (HME) type Improvised Explosive Device (IED), demonstrating the practical challenges, analytical strategies, and investigative value of integrated chemical and trace evidence analysis in post-blast homicide investigations. Case Background On the day of the incident, the victim went to the field for cultivation. The suspect, along with others surrounded the victim with deadly weapons and bombs. When the victim tried to escape, they threw bombs by targeting the victim. The victim was grievously injured on his right hand and ribs, and later died. Local Police with Bomb disposal squad rushed to the crime scene and searched the area for possible clues. They found unexploded live bombs and debris from exploded bombs. The live bombs were disposed of by the bomb disposal squad in a controlled manner. The exhibits collected from the place of occurrence were properly packed, sealed and sent to the laboratory for chemical analysis to identify the explosive residues in the debris. A case was registered against the suspects and four persons were arrested. Materials and Methods Evidence Collection The crime scene was secured, and thorough documentation was conducted. Soil with blood stain and control soil samples were collected systematically from multiple points around the blast epicenter. Suspected explosive fragments of the exploded IED including bundle of Jute thread, Stone chips, broken pieces of metallic containers were recovered and carefully packaged to prevent contamination or loss of residue. Victim's upper & lower clothing and a portion of his burned skin (without preservation) were also taken to detect trace explosive materials. These are given in Figure- 1 to 3. Exhibits preparation The exhibits were received by the laboratory in six different parcels after five months of the incident occurred. The Soil sample were sent to the Biology division for identification of the blood stain and transferred to the Explosive Division for identification of trace elements. The Jute thread, Stone chips, broken pieces of metallic containers, soil samples and skin of the deceased were properly extracted by Ether, Acetone, Water, Sodium Hydroxide and Pyridine for identification of the both In-Organic and Organic Explosive traces. The dresses of the victim were in wet condition with formation of maggots. Hence, water extract taken first and followed by other extracts. Chemicals and Solvents Diethyl Ether was obtained from Finar, Acetone (AR) was obtained from Advent Chembio Pvt. Ltd, Sodium Hydroxide, and Pyridine was obtained from SRL. Demineralized (DM) water procured from Labogen Fine Chem Industry, Ludhiana was used for Water and Alkali extraction. Whatman-42 filter paper was used for its filtration. Allpure Nylon Syringe filter (pore size 0.22 µm) was procured from Membrane Solutions was used for filtration of Ether and Acetone extracts. [ 19 , 20 ] Silica gel 60G F254 Plates with 200 micrometer thickness and Size 20 x 20 cm were used for Thin Layer Chromatography (TLC) analysis. Chloroform, Acetone, Toluene and Cyclo hexane used for the test. Ether Extraction The samples were treated with ether, filtered using syringe filter to remove any solid impurities, the filtrate was collected in a 100ml beaker and concentrated upto 1ml by evaporation in the room temperature. The filtrate was analyzed in the FTIR-ATR for Diesel oil for the identification of Ammonium Nitrate Fuel Oil (ANFO). Acetone Extraction The same samples were treated with acetone after complete evaporation of the ether and filtered using the same syringe filter to remove any solid impurities, the filtrate was collected in the same 100ml beaker and concentrated upto 1ml by evaporation in the room temperature. The filtrate was analyzed by chemical examination, TLC and FTIR with the standard for the identification of Organic Explosives, such as, PETN, TNT, RDX. Water Extraction The same samples were treated with hot distilled water after complete evaporation of the acetone and filtered using the Whatman-42 filter paper to remove any solid impurities, the filtrate was collected in the same 100ml beaker and concentrated upto 10ml. The filtrate was analyzed for In-organic Explosive ions like, Sodium, Potassium, Ammonium, Nitrate, etc. After the Chemical Examination, the remaining extract allowed to dry and the dried sample was analyzed in the FTIR. Alkali Extraction The same samples were treated with 2N Sodium Hydroxide, filtered using the same Whatman-42 filter paper to remove any solid impurities, the filtrate was collected in the same 100ml beaker and concentrated upto 10ml. The extract was tested for metallic Aluminium, Arsenic and Sulphide ions. Pyridine Extraction The same samples were treated with Pyridine, filtered using the same Whatman-42 filter paper to remove any solid impurities, the filtrate was collected in the same 100ml beaker and concentrated upto 1ml. Taken in a small test tube, slightly boiled and a drop of 2N Sodium Hydroxide was added to identify Elemental Sulphur. Thin Layer Chromatography Pre-coated TLC plates were activated by placing them in an air oven at 110°C for 30 minutes. One hundred ml of solvent [chloroform : acetone (1:1) and toluene : cyclohexane (7:3)] was taken in two different developing chambers (for 20 × 20 cm TLC plates), covered with a lid, and allowed to saturate for at least 30 minutes. The concentrated acetone extract of each sample was spotted on the pre-coated TLC plate along with reference standards of high explosives, leaving 2 cm from one edge at the bottom of the TLC plate and maintaining a minimum distance of 1.5 cm between two spots. The TLC plate was placed vertically in the developing chamber and allowed to develop until the solvent front rose to 10 cm from the spots by capillary action. After completion, the plate was removed and left at room temperature for the eluent to evaporate. The TLC plate was developed by spraying with 5% diphenylamine (DPA) in 95% ethanol, and the colour produced was noted. The plate was then placed under UV light (254 nm) to observe fluorescence and subsequently sprayed with concentrated sulphuric acid, with the resulting colours recorded. The colours were compared with the Rf values given in Table 1 . Table 1 Rf values with various solvents and colour of spot for Organic Explosives Compound Colour Development Rf Values in Different Solvent Systems. DPA UV light Sulphuric Acid Griess Reagent Trichloro- ethylene : Acetone (4:1) Chloro- form : Acetone (1:1) Toluene : Cyclo- hexane (7:3) Toluene : Ethyl -acetate (9:1) NG No colour Grayto Green Blue-gray Pink 0.47 --- 0.42 0.66 RDX No colour Gray Blue-gray Red 0.15 0.47 0.03 0.13 PETN No colour Grayto Green Blue-green Red 0.55 0.69 0.45 0.78 TNT Orange Brown Orange Brown Colour fades Brown 0.59 --- 0.57 0.88 TETRYL Brown Brown Yellowto Blue-gray Red 0.40 0.66 0.25 0.61 HMX No colour No colour No colour Red --- 0.40 --- --- Table 2 Observations of the Chemical Examinations Sl.No Chemical Test Target Ion/Analyte Observation 1 Silver Nitrate Chloride Present 2 Griess Test Nitrite Present 3 Griess reagent + Zn dust Nitrate Present 4 Aniline sulphate Chlorate Absent 5 Methylene blue indicator Perchlorate Absent 6 Barium chloride Sulphate Present 7 Zinc Uranyl Acetate Sodium Absent 8 Sodium Cobaltinitrate Potassium Present 9 Nessler’s reagent Ammonium Present 10 Magneson-I Magnesium Absent 11 Sodium Rhodizonate Barium, Calcium, Strontium Absent 12 Sodium Nitroprusside Sulphide (NaOH Extract) Absent 13 Alizarine-S Metallic Aluminium (NaOH Extract) Present 14 Gutzeit’s Test Arsenic (NaOH Extract) Absent 15 Pyridine + NaOH Elemental Sulphur Present Fourier transform infrared spectroscopy (FTIR) The Ether extract, Acetone extract and dried samples of the water extract were examined in the Thermo Fisher Scientific Nicolet iS20 FTIR spectrometer instrument, which equipped with an IR source, an attenuated total reflectance (ATR) accessory, a DTGS detector and KBr beam splitter from Thermo Fisher Scientific. The instrument was operated at resolution of 4.000 between wavenumber 4000 cm-1 to 400 cm-1. The analysis was done by scanning background and sample using Thermo Scientific OMNIC software. The sample was scanned for 64 times and a characteristic spectrum was obtained. The spectrum was searched using correlation search type in the libraries of the instrument to identify the sample.[ 19 , 20 ] Challenges in the analysis of Exhibits The victim’s clothing was wet, with maggot formation, and it was not possible to take swabs from the charred parts or cut a portion. It was treated with ether, and the ether and water extracts were separated using a separating funnel and filtered. In the same manner, the clothing was treated with acetone, and the acetone and water extracts were separated and filtered. Since the volume of ether, acetone, and water filtrates was high, they were carefully concentrated at room temperature as well as through boiling. The skin sample was in a shrunken condition and was thoroughly mixed with ether and stirred with a glass rod for complete recovery of both high and low explosives. The extract was filtered and analyzed. The same procedure was followed for acetone, water, sodium hydroxide, and pyridine extractions. Observations Chemical Examinations There was no significant presence of High Explosives observed in the Acetone Extract. The Low Explosives identified in the Water, Alkali and Pyridine extracts are given in the Table-2 Except for the control soil, all the exhibits gave positive results for low explosives. TLC Analysis No specific High Explosives were observed in the TLC analysis of Acetone Extract. FTIR Analysis No significant High Explosives and Diesel Fuel present in the FTIR analysis of Acetone Extract and Ether Extract. However, Potassium Nitrate and Ammonium Nitrate (Low Explosives) were identified in the Water Extract. The FTIR spectrum were given in the Figure-4 and Figure-5. Results and Discussion The forensic examination of the exhibits revealed the predominance of low explosive residues, with no detectable high explosive components in either acetone or ether extracts. Chemical analysis confirmed the presence of nitrate, nitrite, chloride, sulphate, potassium, ammonium, metallic aluminium, and elemental sulphur in the water, alkali, and pyridine extracts from multiple exhibits, excluding the control soil sample. These findings are consistent with the formulation of improvised low explosive mixtures, particularly those incorporating potassium nitrate or ammonium nitrate as oxidizers, metallic aluminium as a fuel sensitizer, and sulphur as an additional combustible component [ 1 , 4 , 9 ]. The cumulative observation of the ions detection by the Chemical Examination is given in the Fig-6. LC analysis did not yield detectable high explosive signatures, further supporting the conclusion that the device employed was based on low explosive chemistry. FTIR examination corroborated the presence of potassium nitrate and ammonium nitrate in water extracts, with distinct absorption bands corresponding to nitrate functional groups, while no diesel fuel or organic high explosive peaks were identified. This analytical outcome rules out ANFO-type explosives, despite the detection of nitrate salts [ 2 , 5 , 10 ]. The combined evidence profile aligns with common homemade explosive (HME) formulations, such as mixtures of potassium nitrate, sulphur, and aluminium powder, which are known to produce significant blast effects in confined or semi-confined configurations [ 3 , 8 ]. The recovery of metallic container fragments, stone chips, and jute thread suggests the use of a fragmentation-oriented improvised explosive device (IED), designed to increase lethality through the dispersion of shrapnel [ 6 , 11 ]. An important aspect of this investigation was the challenging condition of the exhibits. The victim’s clothing was received in a decomposed state with maggot infestation and retained moisture, while the skin sample was shrunken and thermally altered. Despite these adverse preservation conditions and the five-month delay between incident and laboratory receipt, careful sequential solvent extraction enabled recovery of detectable residues. This underlines the robustness of the applied extraction and analytical protocols in recovering forensic evidence even under conditions of significant degradation [ 7 , 9 ]. From an investigative standpoint, the analytical confirmation of specific chemical constituents provided critical information for reconstructing the device composition and corroborating witness accounts of the blast mechanism. The absence of high explosive residues also has legal and operational implications, narrowing the scope of possible explosive precursors and focusing the investigation towards locally accessible materials [ 1 , 4 , 12 ]. Conclusion This case study demonstrates the practical challenges and scientific strategies in post-blast forensic analysis of a homicide involving an improvised low explosive device. The integrated use of chemical testing, TLC, and FTIR enabled the identification of potassium nitrate, ammonium nitrate, metallic aluminium, and sulphur, establishing the presence of a nitrate-based HME formulation [ 2 , 4 , 10 ]. The absence of high explosives and diesel fuel in the recovered residues indicated the use of a low explosive mixture, likely combined with shrapnel materials to enhance lethality [ 3 , 8 ]. The successful recovery of explosive residues from highly degraded exhibits, including decomposed clothing and thermally altered human tissue, illustrates the effectiveness of sequential solvent extraction in post-blast investigations [ 7 , 9 ]. The correlation of analytical results with physical evidence such as metallic fragments, stone chips, and jute thread provided a comprehensive reconstruction of the device design and operational intent [ 6 , 11 ]. Overall, the findings underscore the importance of systematic evidence collection, appropriate extraction protocols, and multi-technique analytical approaches in overcoming the limitations posed by environmental degradation and delayed evidence submission [ 1 , 4 , 12 ]. Such methodologies are vital in supporting both investigative leads and prosecutorial outcomes in explosive-related homicide cases. Declarations Ethics approval Ethical approval was not applicable, as the forensic examination (including the related court deposition) was conducted as part of routine medico-legal duty and had already been completed prior to manuscript preparation. No additional research interventions were undertaken, in accordance with COPE-based ethical guidance. Consent to participate Consent to participate was waived, as the case involves a deceased individual and all identifying details have been anonymized. This approach is consistent with institutional policy, journal requirements, and COPE-based ethical guidance. Consent for publication Consent for publication was waived, as the case involves a deceased individual and all identifying details have been anonymized. This approach is consistent with institutional policy, journal requirements, and COPE-based ethical guidance. Clinical trial number Not applicable Funding None Author Contribution Conceptualization, D.K.; methodology, D.K.; validation, D.K.; formal analysis, D.K.; investigation, D.K.; writing—original draft preparation, D.K.; writing—review and editing, D.K.; visualization, D.K.; and supervision, D.K. The author has read and agreed to the published version of this manuscript. Acknowledgement I would like to express my gratitude to the Director, Central Forensic Science Laboratory, Pune, for continuous support and for providing the necessary infrastructure for this study. Data Availability The author declares that the data supporting the findings of this study are available within the paper. Should any raw data files be needed in another format, they are available from the author upon reasonable request. References Yinon J (1999) Forensic and Environmental Detection of Explosives. CRC Beveridge A (2011) Forensic Investigation of Explosions, 2nd edn. CRC Kumar A, Sharma R, Singh S (2008) Analysis of low explosive residues from post-blast debris. Forensic Sci Int 177(1):42–49 Yinon J, Zitrin S (1993) Modern Methods and Applications in Analysis of Explosives. Wiley Bell S et al (2016) Forensic applications of FTIR spectroscopy. Forensic Sci Rev 28(2):145–166 Gross SR et al (2012) Fragmentation patterns in IED-related fatalities. J Forensic Sci 57(5):1235–1241 Douse JM (1985) Sampling and analysis of explosives residues in post-blast scenes. J Energetic Mater 3(1):1–25 Akhavan J (2011) The Chemistry of Explosives, 3rd edn. RSC Publishing Jenkins TF et al (2006) Environmental degradation of explosive residues. Chemosphere 63(9):1460–1471 Yinon J (2002) Detection of explosives by spectroscopic techniques. Talanta 54(3):501–514 Raza M et al (2015) Forensic reconstruction of improvised explosive devices. Def Sci J 65(4):300–306 Gardos MN, Schubert H (1990) Forensic exploitation of explosive materials. Propellants Explos Pyrotech 15(2):51–56 Beveridge AD (2021) Forensic Investigation of Explosions. CRC García-Ruiz C, Torre M, García J (2013) Analytical techniques in post-blast investigation: A review. TRAC Trends Anal Chem 54:36–43 Murray KK, Boyd RK, Eberlin MN, Langley GJ, Li L, Naito Y (2018) Definitions of terms relating to mass spectrometry (IUPAC Recommendations 2013). Pure Appl Chem 85(7):1515–1609 Ruffell A, McKinley J (2005) Forensic geomorphology. Geomorphology 67(1–2):3–12 Sigman ME, Clark CD, Williams MR (2014) Forensic analysis of explosives residues. Anal Bioanal Chem 406(21):5331–5345 Yinon J, Zitrin S (1996) Modern Methods and Applications in Analysis of Explosives. Wiley Prajakta KD U.K. Optimizing Forensic Detection of Explosive Substances: Extended Column Analysis of TNT. Int J Res Appl Sci & Engineering Technology (IJRASET). https://doi.org/10.22214/ijraset.2025.71458 Prajakta KD U.K. Thermal Decomposition Approach for PETN Detection in Improvised Explosive Devices. International Journal of Innovative Research in Technology (IJIRT). May 2025 | IJIRT | 11 Issue 12 | ISSN: 2349–6002. https://doi.org/10.64643/IJIRTV12I3-179451-457 Abbreviations IED Improvised Explosive Device HME Homemade Explosives TLC Thin Layer Chromatography FTIR Fourier Transform Infrared Spectroscopy AR Analytical Reagent DM De-Mineralized ATR Attenuated Total Reflectance ANFO Ammonium Nitrate Fuel Oil PETN Penta Erythritol Tetra Nitrate TNT Tri Nitro Toluene RDX Research Department Explosive/ Royal Demolition Explosive NG Nitro Glycerin TETRYL Trinitrophenylmethylnitramine HMX High Melting eXplosive - Octogen DPA Di Phenyl Amine UV Ultra Violet DTGS Deuterated Tri Glycine Sulfate IR Infra Red NaOH Sodium Hydroxide Additional Declarations No competing interests reported. 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1","display":"","copyAsset":false,"role":"figure","size":6249,"visible":true,"origin":"","legend":"\u003cp\u003eBurned Skin of the victim\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7365009/v2/8d1df44ab45ae242e3dd7fca.jpeg"},{"id":92683017,"identity":"b642d60e-130b-4d26-ab98-a92f4623af93","added_by":"auto","created_at":"2025-10-03 01:27:56","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":350111,"visible":true,"origin":"","legend":"\u003cp\u003eDress of the Victim\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7365009/v2/d92bd19bbf9db75f51058f48.jpeg"},{"id":92682286,"identity":"5fedc2eb-9f87-495e-ad02-c55f65144164","added_by":"auto","created_at":"2025-10-03 01:11:56","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":387546,"visible":true,"origin":"","legend":"\u003cp\u003eBroken metallic container, Jute thread and Stone chips\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7365009/v2/b39aef1742e405c550a765a5.jpeg"},{"id":92682657,"identity":"055d8a86-2101-42bd-97a9-e479898e90ba","added_by":"auto","created_at":"2025-10-03 01:19:55","extension":"jpeg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":69528,"visible":true,"origin":"","legend":"\u003cp\u003eFTIR spectrum of the sample (top) and its library match (bottom)\u003c/p\u003e","description":"","filename":"floatimage4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7365009/v2/d6fc4ed11bc2c24cd438e38c.jpeg"},{"id":92683014,"identity":"657fc09d-3a31-4eb5-89f2-a699eed55fbf","added_by":"auto","created_at":"2025-10-03 01:27:55","extension":"jpeg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":67188,"visible":true,"origin":"","legend":"\u003cp\u003eFTIR spectrum of the sample (top) and its library match (bottom)\u003c/p\u003e","description":"","filename":"floatimage5.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7365009/v2/657c9e822cf44cf4d1a5edf5.jpeg"},{"id":92683016,"identity":"503191df-b415-4c36-9265-897268dc6376","added_by":"auto","created_at":"2025-10-03 01:27:55","extension":"jpeg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":29019,"visible":true,"origin":"","legend":"\u003cp\u003eObservation of Ions by the Chemical Examination\u003c/p\u003e","description":"","filename":"floatimage6.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7365009/v2/fe69c8f16d2cad92cd5f3dba.jpeg"},{"id":92683399,"identity":"b9444225-e764-4788-8c44-66ba057fd9ca","added_by":"auto","created_at":"2025-10-03 01:43:58","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1624523,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7365009/v2/424c16ba-ecd2-477e-8d4b-5becce0c227b.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Explosive Device Reconstruction through Chemical and Trace Evidence Analysis: A Homicide Case Investigation","fulltext":[{"header":"Introduction","content":"\u003cp\u003eExplosive-related homicides are among the most complex cases in forensic science, largely because of the destructive nature of blast events and the consequent fragmentation and dispersion of physical evidence. Post-blast environments often contain commingled debris, vaporized or thermally altered residues, and trace particulates that may be present in minute quantities and subject to rapid environmental degradation [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. The recovery, preservation, and accurate analysis of these traces are critical for reconstructing the sequence of events, determining the type and origin of the explosive used, and establishing evidentiary links between the device, the scene, and potential suspects [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Achieving this requires a multidisciplinary approach, combining systematic scene processing, chemical characterization, and trace evidence examination [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Recent advances in analytical techniques, including Thin Layer Chromatography (TLC), Fourier Transform Infrared Spectroscopy (FTIR), and other spectrometric and chromatographic methods, have significantly enhanced the detection sensitivity and specificity for explosive residues, even in complex post-blast matrices [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. This study applies such a combined forensic methodology to a fatal case involving a Homemade Explosives (HME) type Improvised Explosive Device (IED), demonstrating the practical challenges, analytical strategies, and investigative value of integrated chemical and trace evidence analysis in post-blast homicide investigations.\u003c/p\u003e"},{"header":"Case Background","content":"\u003cp\u003eOn the day of the incident, the victim went to the field for cultivation. The suspect, along with others surrounded the victim with deadly weapons and bombs. When the victim tried to escape, they threw bombs by targeting the victim. The victim was grievously injured on his right hand and ribs, and later died.\u003c/p\u003e\u003cp\u003eLocal Police with Bomb disposal squad rushed to the crime scene and searched the area for possible clues. They found unexploded live bombs and debris from exploded bombs. The live bombs were disposed of by the bomb disposal squad in a controlled manner. The exhibits collected from the place of occurrence were properly packed, sealed and sent to the laboratory for chemical analysis to identify the explosive residues in the debris. A case was registered against the suspects and four persons were arrested.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\u003ch2\u003eEvidence Collection\u003c/h2\u003e\u003cp\u003eThe crime scene was secured, and thorough documentation was conducted. Soil with blood stain and control soil samples were collected systematically from multiple points around the blast epicenter. Suspected explosive fragments of the exploded IED including bundle of Jute thread, Stone chips, broken pieces of metallic containers were recovered and carefully packaged to prevent contamination or loss of residue. Victim's upper \u0026amp; lower clothing and a portion of his burned skin (without preservation) were also taken to detect trace explosive materials. These are given in Figure- 1 to 3.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eExhibits preparation\u003c/h3\u003e\n\u003cp\u003eThe exhibits were received by the laboratory in six different parcels after five months of the incident occurred. The Soil sample were sent to the Biology division for identification of the blood stain and transferred to the Explosive Division for identification of trace elements. The Jute thread, Stone chips, broken pieces of metallic containers, soil samples and skin of the deceased were properly extracted by Ether, Acetone, Water, Sodium Hydroxide and Pyridine for identification of the both In-Organic and Organic Explosive traces. The dresses of the victim were in wet condition with formation of maggots. Hence, water extract taken first and followed by other extracts.\u003c/p\u003e\n\u003ch3\u003eChemicals and Solvents\u003c/h3\u003e\n\u003cp\u003eDiethyl Ether was obtained from Finar, Acetone (AR) was obtained from Advent Chembio Pvt. Ltd, Sodium Hydroxide, and Pyridine was obtained from SRL. Demineralized (DM) water procured from Labogen Fine Chem Industry, Ludhiana was used for Water and Alkali extraction. Whatman-42 filter paper was used for its filtration. Allpure Nylon Syringe filter (pore size 0.22 \u0026micro;m) was procured from Membrane Solutions was used for filtration of Ether and Acetone extracts. [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/p\u003e\u003cp\u003eSilica gel 60G F254 Plates with 200 micrometer thickness and Size 20 x 20 cm were used for Thin Layer Chromatography (TLC) analysis. Chloroform, Acetone, Toluene and Cyclo hexane used for the test.\u003c/p\u003e\n\u003ch3\u003eEther Extraction\u003c/h3\u003e\n\u003cp\u003eThe samples were treated with ether, filtered using syringe filter to remove any solid impurities, the filtrate was collected in a 100ml beaker and concentrated upto 1ml by evaporation in the room temperature. The filtrate was analyzed in the FTIR-ATR for Diesel oil for the identification of Ammonium Nitrate Fuel Oil (ANFO).\u003c/p\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003eAcetone Extraction\u003c/h2\u003e\u003cp\u003eThe same samples were treated with acetone after complete evaporation of the ether and filtered using the same syringe filter to remove any solid impurities, the filtrate was collected in the same 100ml beaker and concentrated upto 1ml by evaporation in the room temperature. The filtrate was analyzed by chemical examination, TLC and FTIR with the standard for the identification of Organic Explosives, such as, PETN, TNT, RDX.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eWater Extraction\u003c/h3\u003e\n\u003cp\u003eThe same samples were treated with hot distilled water after complete evaporation of the acetone and filtered using the Whatman-42 filter paper to remove any solid impurities, the filtrate was collected in the same 100ml beaker and concentrated upto 10ml. The filtrate was analyzed for In-organic Explosive ions like, Sodium, Potassium, Ammonium, Nitrate, etc. After the Chemical Examination, the remaining extract allowed to dry and the dried sample was analyzed in the FTIR.\u003c/p\u003e\n\u003ch3\u003eAlkali Extraction\u003c/h3\u003e\n\u003cp\u003eThe same samples were treated with 2N Sodium Hydroxide, filtered using the same Whatman-42 filter paper to remove any solid impurities, the filtrate was collected in the same 100ml beaker and concentrated upto 10ml. The extract was tested for metallic Aluminium, Arsenic and Sulphide ions.\u003c/p\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003ePyridine Extraction\u003c/h2\u003e\u003cp\u003eThe same samples were treated with Pyridine, filtered using the same Whatman-42 filter paper to remove any solid impurities, the filtrate was collected in the same 100ml beaker and concentrated upto 1ml. Taken in a small test tube, slightly boiled and a drop of 2N Sodium Hydroxide was added to identify Elemental Sulphur.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003eThin Layer Chromatography\u003c/h2\u003e\u003cp\u003ePre-coated TLC plates were activated by placing them in an air oven at 110\u0026deg;C for 30 minutes. One hundred ml of solvent [chloroform : acetone (1:1) and toluene : cyclohexane (7:3)] was taken in two different developing chambers (for 20 \u0026times; 20 cm TLC plates), covered with a lid, and allowed to saturate for at least 30 minutes. The concentrated acetone extract of each sample was spotted on the pre-coated TLC plate along with reference standards of high explosives, leaving 2 cm from one edge at the bottom of the TLC plate and maintaining a minimum distance of 1.5 cm between two spots. The TLC plate was placed vertically in the developing chamber and allowed to develop until the solvent front rose to 10 cm from the spots by capillary action. After completion, the plate was removed and left at room temperature for the eluent to evaporate.\u003c/p\u003e\u003cp\u003eThe TLC plate was developed by spraying with 5% diphenylamine (DPA) in 95% ethanol, and the colour produced was noted. The plate was then placed under UV light (254 nm) to observe fluorescence and subsequently sprayed with concentrated sulphuric acid, with the resulting colours recorded. The colours were compared with the Rf values given in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eRf values with various solvents and colour of spot for Organic Explosives\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"9\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eCompound\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e\u003cp\u003eColour Development\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"4\" nameend=\"c9\" namest=\"c6\"\u003e\u003cp\u003eRf Values in Different Solvent Systems.\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDPA\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eUV light\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSulphuric\u003c/p\u003e\u003cp\u003eAcid\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eGriess\u003c/p\u003e\u003cp\u003eReagent\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eTrichloro-\u003c/p\u003e\u003cp\u003eethylene : Acetone (4:1)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eChloro-\u003c/p\u003e\u003cp\u003eform : Acetone (1:1)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eToluene\u003c/p\u003e\u003cp\u003e: Cyclo- hexane (7:3)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e\u003cp\u003eToluene\u003c/p\u003e\u003cp\u003e: Ethyl -acetate (9:1)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNo colour\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eGrayto\u003c/p\u003e\u003cp\u003eGreen\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eBlue-gray\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003ePink\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e---\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.42\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.66\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRDX\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNo colour\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eGray\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eBlue-gray\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eRed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.03\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.13\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePETN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNo colour\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eGrayto\u003c/p\u003e\u003cp\u003eGreen\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eBlue-green\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eRed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.55\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.69\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.78\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTNT\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eOrange\u003c/p\u003e\u003cp\u003eBrown\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eOrange\u003c/p\u003e\u003cp\u003eBrown\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eColour fades\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eBrown\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.59\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e---\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.57\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.88\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTETRYL\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eBrown\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eBrown\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eYellowto\u003c/p\u003e\u003cp\u003eBlue-gray\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eRed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.66\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.61\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHMX\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNo colour\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eNo colour\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eNo colour\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eRed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e---\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e---\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e---\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eObservations of the Chemical Examinations\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSl.No\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eChemical Test\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eTarget Ion/Analyte\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eObservation\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSilver Nitrate\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eChloride\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePresent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eGriess Test\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eNitrite\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePresent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eGriess reagent\u0026thinsp;+\u0026thinsp;Zn dust\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eNitrate\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePresent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAniline sulphate\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eChlorate\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAbsent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMethylene blue indicator\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003ePerchlorate\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAbsent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eBarium chloride\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSulphate\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePresent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eZinc Uranyl Acetate\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSodium\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAbsent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSodium Cobaltinitrate\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003ePotassium\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePresent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNessler\u0026rsquo;s reagent\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAmmonium\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePresent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMagneson-I\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMagnesium\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAbsent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSodium Rhodizonate\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eBarium, Calcium, Strontium\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAbsent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSodium Nitroprusside\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSulphide (NaOH Extract)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAbsent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAlizarine-S\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMetallic Aluminium (NaOH Extract)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePresent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eGutzeit\u0026rsquo;s Test\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eArsenic (NaOH Extract)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAbsent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePyridine\u0026thinsp;+\u0026thinsp;NaOH\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eElemental Sulphur\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePresent\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\u003ch2\u003eFourier transform infrared spectroscopy (FTIR)\u003c/h2\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003eThe Ether extract, Acetone extract and dried samples of the water extract were examined in the Thermo Fisher Scientific Nicolet iS20 FTIR spectrometer instrument, which equipped with an IR source, an attenuated total reflectance (ATR) accessory, a DTGS detector and KBr beam splitter from Thermo Fisher Scientific. The instrument was operated at resolution of 4.000 between wavenumber 4000 cm-1 to 400 cm-1. The analysis was done by scanning background and sample using Thermo Scientific OMNIC software. The sample was scanned for 64 times and a characteristic spectrum was obtained. The spectrum was searched using correlation search type in the libraries of the instrument to identify the sample.[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\u003ch2\u003eChallenges in the analysis of Exhibits\u003c/h2\u003e\u003cp\u003eThe victim\u0026rsquo;s clothing was wet, with maggot formation, and it was not possible to take swabs from the charred parts or cut a portion. It was treated with ether, and the ether and water extracts were separated using a separating funnel and filtered. In the same manner, the clothing was treated with acetone, and the acetone and water extracts were separated and filtered. Since the volume of ether, acetone, and water filtrates was high, they were carefully concentrated at room temperature as well as through boiling.\u003c/p\u003e\u003cp\u003eThe skin sample was in a shrunken condition and was thoroughly mixed with ether and stirred with a glass rod for complete recovery of both high and low explosives. The extract was filtered and analyzed. The same procedure was followed for acetone, water, sodium hydroxide, and pyridine extractions.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\u003ch2\u003eObservations\u003c/h2\u003e\u003cdiv id=\"Sec16\" class=\"Section3\"\u003e\u003ch2\u003eChemical Examinations\u003c/h2\u003e\u003cp\u003eThere was no significant presence of High Explosives observed in the Acetone Extract. The Low Explosives identified in the Water, Alkali and Pyridine extracts are given in the Table-2\u003c/p\u003e\u003cp\u003eExcept for the control soil, all the exhibits gave positive results for low explosives.\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Sec17\" class=\"Section2\"\u003e\u003ch2\u003eTLC Analysis\u003c/h2\u003e\u003cp\u003eNo specific High Explosives were observed in the TLC analysis of Acetone Extract.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec18\" class=\"Section2\"\u003e\u003ch2\u003eFTIR Analysis\u003c/h2\u003e\u003cp\u003eNo significant High Explosives and Diesel Fuel present in the FTIR analysis of Acetone Extract and Ether Extract. However, Potassium Nitrate and Ammonium Nitrate (Low Explosives) were identified in the Water Extract. The FTIR spectrum were given in the Figure-4 and Figure-5.\u003c/p\u003e\u003c/div\u003e"},{"header":"Results and Discussion","content":"\u003cp\u003eThe forensic examination of the exhibits revealed the predominance of low explosive residues, with no detectable high explosive components in either acetone or ether extracts. Chemical analysis confirmed the presence of nitrate, nitrite, chloride, sulphate, potassium, ammonium, metallic aluminium, and elemental sulphur in the water, alkali, and pyridine extracts from multiple exhibits, excluding the control soil sample. These findings are consistent with the formulation of improvised low explosive mixtures, particularly those incorporating potassium nitrate or ammonium nitrate as oxidizers, metallic aluminium as a fuel sensitizer, and sulphur as an additional combustible component [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. The cumulative observation of the ions detection by the Chemical Examination is given in the Fig-6.\u003c/p\u003e\u003cp\u003eLC analysis did not yield detectable high explosive signatures, further supporting the conclusion that the device employed was based on low explosive chemistry. FTIR examination corroborated the presence of potassium nitrate and ammonium nitrate in water extracts, with distinct absorption bands corresponding to nitrate functional groups, while no diesel fuel or organic high explosive peaks were identified. This analytical outcome rules out ANFO-type explosives, despite the detection of nitrate salts [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe combined evidence profile aligns with common homemade explosive (HME) formulations, such as mixtures of potassium nitrate, sulphur, and aluminium powder, which are known to produce significant blast effects in confined or semi-confined configurations [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. The recovery of metallic container fragments, stone chips, and jute thread suggests the use of a fragmentation-oriented improvised explosive device (IED), designed to increase lethality through the dispersion of shrapnel [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eAn important aspect of this investigation was the challenging condition of the exhibits. The victim\u0026rsquo;s clothing was received in a decomposed state with maggot infestation and retained moisture, while the skin sample was shrunken and thermally altered. Despite these adverse preservation conditions and the five-month delay between incident and laboratory receipt, careful sequential solvent extraction enabled recovery of detectable residues. This underlines the robustness of the applied extraction and analytical protocols in recovering forensic evidence even under conditions of significant degradation [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eFrom an investigative standpoint, the analytical confirmation of specific chemical constituents provided critical information for reconstructing the device composition and corroborating witness accounts of the blast mechanism. The absence of high explosive residues also has legal and operational implications, narrowing the scope of possible explosive precursors and focusing the investigation towards locally accessible materials [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis case study demonstrates the practical challenges and scientific strategies in post-blast forensic analysis of a homicide involving an improvised low explosive device. The integrated use of chemical testing, TLC, and FTIR enabled the identification of potassium nitrate, ammonium nitrate, metallic aluminium, and sulphur, establishing the presence of a nitrate-based HME formulation [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. The absence of high explosives and diesel fuel in the recovered residues indicated the use of a low explosive mixture, likely combined with shrapnel materials to enhance lethality [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe successful recovery of explosive residues from highly degraded exhibits, including decomposed clothing and thermally altered human tissue, illustrates the effectiveness of sequential solvent extraction in post-blast investigations [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. The correlation of analytical results with physical evidence such as metallic fragments, stone chips, and jute thread provided a comprehensive reconstruction of the device design and operational intent [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eOverall, the findings underscore the importance of systematic evidence collection, appropriate extraction protocols, and multi-technique analytical approaches in overcoming the limitations posed by environmental degradation and delayed evidence submission [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Such methodologies are vital in supporting both investigative leads and prosecutorial outcomes in explosive-related homicide cases.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval\u003c/strong\u003e\u003cp\u003eEthical approval was not applicable, as the forensic examination (including the related court deposition) was conducted as part of routine medico-legal duty and had already been completed prior to manuscript preparation. No additional research interventions were undertaken, in accordance with COPE-based ethical guidance.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConsent to participate\u003c/strong\u003e\u003cp\u003eConsent to participate was waived, as the case involves a deceased individual and all identifying details have been anonymized. This approach is consistent with institutional policy, journal requirements, and COPE-based ethical guidance.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003cp\u003eConsent for publication was waived, as the case involves a deceased individual and all identifying details have been anonymized. This approach is consistent with institutional policy, journal requirements, and COPE-based ethical guidance.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003ch2\u003eClinical trial number\u003c/h2\u003e\u003cp\u003eNot applicable\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e\u003cp\u003eNone\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eConceptualization, D.K.; methodology, D.K.; validation, D.K.; formal analysis, D.K.; investigation, D.K.; writing\u0026mdash;original draft preparation, D.K.; writing\u0026mdash;review and editing, D.K.; visualization, D.K.; and supervision, D.K. The author has read and agreed to the published version of this manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eI would like to express my gratitude to the Director, Central Forensic Science Laboratory, Pune, for continuous support and for providing the necessary infrastructure for this study.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe author declares that the data supporting the findings of this study are available within the paper. Should any raw data files be needed in another format, they are available from the author upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eYinon J (1999) Forensic and Environmental Detection of Explosives. CRC\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBeveridge A (2011) Forensic Investigation of Explosions, 2nd edn. CRC\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKumar A, Sharma R, Singh S (2008) Analysis of low explosive residues from post-blast debris. Forensic Sci Int 177(1):42\u0026ndash;49\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYinon J, Zitrin S (1993) Modern Methods and Applications in Analysis of Explosives. Wiley\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBell S et al (2016) Forensic applications of FTIR spectroscopy. Forensic Sci Rev 28(2):145\u0026ndash;166\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGross SR et al (2012) Fragmentation patterns in IED-related fatalities. J Forensic Sci 57(5):1235\u0026ndash;1241\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDouse JM (1985) Sampling and analysis of explosives residues in post-blast scenes. J Energetic Mater 3(1):1\u0026ndash;25\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAkhavan J (2011) The Chemistry of Explosives, 3rd edn. RSC Publishing\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eJenkins TF et al (2006) Environmental degradation of explosive residues. Chemosphere 63(9):1460\u0026ndash;1471\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYinon J (2002) Detection of explosives by spectroscopic techniques. Talanta 54(3):501\u0026ndash;514\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRaza M et al (2015) Forensic reconstruction of improvised explosive devices. Def Sci J 65(4):300\u0026ndash;306\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGardos MN, Schubert H (1990) Forensic exploitation of explosive materials. Propellants Explos Pyrotech 15(2):51\u0026ndash;56\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBeveridge AD (2021) Forensic Investigation of Explosions. CRC\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGarc\u0026iacute;a-Ruiz C, Torre M, Garc\u0026iacute;a J (2013) Analytical techniques in post-blast investigation: A review. TRAC Trends Anal Chem 54:36\u0026ndash;43\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMurray KK, Boyd RK, Eberlin MN, Langley GJ, Li L, Naito Y (2018) Definitions of terms relating to mass spectrometry (IUPAC Recommendations 2013). Pure Appl Chem 85(7):1515\u0026ndash;1609\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRuffell A, McKinley J (2005) Forensic geomorphology. Geomorphology 67(1\u0026ndash;2):3\u0026ndash;12\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSigman ME, Clark CD, Williams MR (2014) Forensic analysis of explosives residues. Anal Bioanal Chem 406(21):5331\u0026ndash;5345\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYinon J, Zitrin S (1996) Modern Methods and Applications in Analysis of Explosives. Wiley\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePrajakta KD U.K. Optimizing Forensic Detection of Explosive Substances: Extended Column Analysis of TNT. Int J Res Appl Sci \u0026amp; Engineering Technology (IJRASET). \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.22214/ijraset.2025.71458\u003c/span\u003e\u003cspan address=\"10.22214/ijraset.2025.71458\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePrajakta KD U.K. Thermal Decomposition Approach for PETN Detection in Improvised Explosive Devices. International Journal of Innovative Research in Technology (IJIRT). May 2025 | IJIRT | 11 Issue 12 | ISSN: 2349\u0026ndash;6002. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.64643/IJIRTV12I3-179451-457\u003c/span\u003e\u003cspan address=\"10.64643/IJIRTV12I3-179451-457\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eIED\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Improvised Explosive Device\u003c/p\u003e\n\u003cp\u003eHME\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Homemade Explosives\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTLC\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Thin Layer Chromatography\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFTIR \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Fourier Transform Infrared Spectroscopy\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAR\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Analytical Reagent\u003c/p\u003e\n\u003cp\u003eDM\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;De-Mineralized\u003c/p\u003e\n\u003cp\u003eATR \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Attenuated Total Reflectance\u003c/p\u003e\n\u003cp\u003eANFO\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Ammonium Nitrate Fuel Oil\u003c/p\u003e\n\u003cp\u003ePETN Penta Erythritol Tetra Nitrate\u003c/p\u003e\n\u003cp\u003eTNT\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Tri Nitro Toluene\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eRDX Research Department Explosive/ Royal Demolition Explosive\u003c/p\u003e\n\u003cp\u003eNG\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Nitro Glycerin\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTETRYL \u003cem\u003eTrinitrophenylmethylnitramine\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eHMX\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;High Melting eXplosive - Octogen\u003c/p\u003e\n\u003cp\u003eDPA\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Di Phenyl Amine\u003c/p\u003e\n\u003cp\u003eUV\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Ultra Violet\u003c/p\u003e\n\u003cp\u003eDTGS\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Deuterated Tri Glycine Sulfate\u003c/p\u003e\n\u003cp\u003eIR\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Infra Red\u003c/p\u003e\n\u003cp\u003eNaOH \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Sodium Hydroxide\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Post-Blast analysis, Homemade IED, Homicide investigation, Explosive residues, Forensic Trace evidence","lastPublishedDoi":"10.21203/rs.3.rs-7365009/v2","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7365009/v2","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e\u003cp\u003ePost-blast forensic investigations involving improvised explosive devices (IEDs) pose significant analytical challenges due to the degradation, dispersion, and contamination of explosive residues. This study reports on a homicide case in which a homemade explosive (HME) device was used, focusing on the systematic recovery and chemical analysis of trace evidence from highly degraded exhibits collected five months after the incident.\u003c/p\u003e\u003ch2\u003eCase presentation\u003c/h2\u003e\u003cp\u003eThis study presents a homicide case in which a homemade explosive (HME) device was deployed in an agricultural field, resulting in the death of a single victim. The suspects allegedly used bombs containing fragmentary materials. Evidence, including soil, debris, metallic fragments, jute thread, stone chips, the victim\u0026rsquo;s clothing, and burned skin, was recovered five months after the incident under degraded conditions. Sequential solvent extractions (ether, acetone, water, sodium hydroxide, and pyridine) were performed, followed by chemical tests, Thin Layer Chromatography (TLC), and Fourier Transform Infrared Spectroscopy (FTIR). Analytical results confirmed the presence of low explosive constituents\u0026mdash;potassium nitrate, ammonium nitrate, metallic aluminium, and elemental sulphur\u0026mdash;in multiple exhibits. No high explosives or diesel fuel were detected. Physical evidence supported the use of a fragmentation-oriented IED, designed to increase lethality through shrapnel dispersal. Despite significant sample decomposition, maggot infestation, and thermal alteration, the adopted protocols enabled the reliable detection of explosive residues, aiding in the reconstruction of the device and corroborating witness statements.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eThis investigation demonstrated the effectiveness of integrated chemical analysis and trace evidence examination in post-blast homicide cases, even with heavily degraded samples and delayed submission. The combination of sequential extraction methods and multi-technique instrumental analysis provided robust and probative findings, confirming the use of nitrate-based HME with added fragmentation materials. This case highlights the importance of meticulous evidence collection, comprehensive analytical approaches, and adaptability of forensic protocols to challenging post-blast scenarios, thereby enhancing investigative and prosecutorial outcomes in explosive-related crimes.\u003c/p\u003e","manuscriptTitle":"Explosive Device Reconstruction through Chemical and Trace Evidence Analysis: A Homicide Case Investigation","msid":"","msnumber":"","nonDraftVersions":[{"code":2,"date":"2025-10-03 01:11:51","doi":"10.21203/rs.3.rs-7365009/v2","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}},{"code":1,"date":"2025-08-18 08:20:45","doi":"10.21203/rs.3.rs-7365009/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"49580c98-0e79-44db-a6f3-f770893eb414","owner":[],"postedDate":"October 3rd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-10-03T01:11:53+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-03 01:11:51","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v2","identity":"rs-7365009","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7365009","identity":"rs-7365009","version":["v2"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}