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Kubang Kerian, Kelantan State, Malaysia. 2Forensic Scientific Officer, Forensic Unit, Kota Kinabalu, Sabah, Malaysia. 3Assistant ..... Armed Forces Journal.
COLLEGE SADHANA - Journal for Bloomers of Research,

Vol. 5,

No. 2,

FEBRUARY 2013

Identification of Explosives in Improvised Explosive Device (IED) Explosions for use in Crime Scene Investigation T. Nataraja Moorthy1, Reynold Vicente2, Ariffin Bin Haron3 and Sivabalan Nagayah4 1

Senior Lecturer in Forensic Sciences, School of Health Sciences, Universiti Sains Malaysia, 16150, Health Campus, Kubang Kerian, Kelantan State, Malaysia 2

Forensic Scientific Officer, Forensic Unit, Kota Kinabalu, Sabah, Malaysia.

3

Assistant Forensic Consultant Approved Forensics, Selangor Darul Ehsan, Malaysia.

4

Forensic Scientific Officer, Explosive division, Forensic Science Unit, JKM, Selangor, Malaysia.

Abstract - Bombs and Improvised Explosive Device (IED) are nightmare to peace loving people and security agencies. Examination of bomb crime scene is an area of increasing involvement for the forensic scientists in which incidents may vary from student mischief to mass murder. IED or a criminal bomb means explosive devices planted or delivered with the intention of causing injury, death and damage to property. The IED could be in any size and shape filled with any type of explosive chemicals. The study was aimed to conduct explosions with different types of IED and identify the explosive for crime reconstruction. Keywords – Forensic science; IED explosion; explosive identification; crime investigation.

1. INTRODUCTION In the recent years, terrorist activity has increased throughout the world. Fire and explosive are two of the weapons in the terrorist’s arsenal. These tools are not only used for the primary goal of effecting an irreparable loss against the enemy, but may many times be used as a diversionary tactic, method of gaining money through insurance fraud, and others. An explosive may be defined as a single chemical compound or a mixture of substances which, when suitably initiates, suffer rapid decomposition with liberation of heat and production of large volumes of gas at high pressure. They may be solid, liquid or gaseous substances [1]. Example includes gun powder or black powder, Trinitrotolune (TNT), Nitroglycerine, Pentaerythritoltetranitrate (PETN), Mercury fulminate, Picric acid (TNP), Cyclotrimethylenetrinitramine (RDX), ANFO (ammonium nitrate and fuel oil) and so on. An explosion is derived from the explosive and defined as the sudden rapid escape of gases from a confined place, with high pressure, temperature, violent shock and loud noise [2].

Thus an explosive is a substance that can produce an explosion through a chemical reaction. When it is used illegally and to cause harm it is generally known as a bomb. Legitimate explosives include fireworks and blasting materials used in quarrying. Explosives generally contain fuel and an oxidant and it is the chemical reaction between them which releases stored chemical energy. There are two kinds of explosive: low or low power explosive and high or high power explosive. Low explosives do not detonate but burn i.e. change from a solid to a gaseous state slowly exert throwing or pushing effect (400 m/sec) and many of them are inorganic. The high explosives detonate i.e. change from solid to a gaseous state almost instantaneously and the velocity of “explosive shock front” range from 3000 to 9000 m/sec. High explosives are mostly organic and much more dangerous, having more of scattering effect on the target. Improvised Explosive Device (IED): Improvised Explosive Device (IED) is any device that is made from materials that are either at hand or are easy to acquire [3]. It is defined as an explosive device that is placed or fabricated in an improvised manner; incorporates destructive, lethal, noxious, pyrotechnic, or incendiary chemicals; and is designed to destroy, incapacitate, harass, or distract. They are as varied as “commanddetonated” pipe bombs, “booby-trapped” military ordnance, and car bombs. The IED has proved to be a cheap, relatively easy-to-use tool against both civilians and advanced militaries. The first nine months of 2011 saw an average of 608 IED attacks per month in 99 countries, according to the Defense Department, US. [4]. 637

COLLEGE SADHANA - Journal for Bloomers of Research,

Vol. 5,

The forensic science community is interested in examining the blasting scenes and analyzing post-blast explosive residues, chemicals and materials associated with bomb making [5]. Of the improvised explosive devices used in illegal activity pipe bombs are a dominant configuration [6]. The current trend is the problem of the misuse of widely available chemicals such as ammonium nitrate as precursors to homemade explosives [7]. The author (TN) had visited many explosion crime scenes involving IEDs and guided the police officers in crime scene investigation and even some incidents had appeared in daily news in India (Fig 1). This research was aimed to blast IED explosives with varying quantities of low explosive (Pyrotechnics) and high power explosive (Plastic explosive) with different containers and to identify the chemicals and debris by chemical and instrumentation analysis for the crime scene reconstruction.

No. 2,

FEBRUARY 2013

2. MATERIALS AND METHODS Place of blasting exercise and officers involved: The project was designed by the author (TN) and the IED blasting exercise was conducted at Chenderiang, Perak state, Malaysia (Fig 2) as decided by the Royal Malaysian Police (PDRM).

The bomb detection and disposal team, headed by Mr.Soo Me Tong, Supdt of Police and DSP Taman, Cheras and Perak Bomb disposal Unit headed by Inspr. Mohd Faisal Bin Abdul Ghani, were involved in this laborious and tedious blasting exercise (Fig 3,4).

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T. Nataraja Moorthy, Reynold Vicente, Ariffin Bin Haron and Sivabalan Nagayah - Identification of Explosives in Improvised Explosive Device (IED) Explosions for use in Crime Scene Investigation

The soil surface of the blasting site was more compact and hard and the geology of Perak area is underline by an extensive limestone bedrock formation (8).

understanding, analysis and result of soil sample collected at the seat of explosion alone is described.

There are seven types of IEDs were prepared with varying containers viz. cloth with black stationery tape packing, plastic pipes and iron pipe (Fig 5) and varying quantities of high (plastic explosive) and low power (Pyrotechnics) explosives as shown in Table 1. The explosion exercises were conducted following the standard operation procedure of Royal Malaysian Police technique. The PostBlast Investigation (PBI) of the Royal Malaysian Police technique is based on the 10person concept as in Bureau of Alcohol, Tobacco and Firearms (ATF), USA. After an explosion exercise, the entire crime scene was documented by photography and crime scene sketch covering all the scientific evidences. The post blast samples were collected in the blasting site using appropriate tools (Fig 6) and the evidence materials include soil samples at the seat of explosion or the epicenter, control soil samples, crater material, bomb components and fragments, material used to construct the explosive devices, residue and other trace evidence. The evidences were collected by parallel search pattern and the collected samples were packaged and preserved and labeled. The collected scientific evidence was taken to Forensic Science Laboratory, Chemistry Department of Malaysia, Selangor, and conducted the chemical and instrumentation analysis. Even though analysis were conducted on all post blast debris collected in the blasting site, for easy Table 1: Containers and quantity of explosives used for the blasting IED No.

Explosive type

Container

Mass of container (g)

Mass of explosive Chemical (g)

Mass of packing material (g)

Total mass of IED (g)

1 2 3 4 5 6 7

Low power Low power High power High power High power Low power High power

Clothes PVC pipe PVC pipe Clothes PVC pipe PVC pipe Iron pipe

60.0 150.0 150.0 60.0 150.0 150.0 1690.0

200.0 150.0 150.0 200.0 300.0 300.0 300.0

90 50 50 90 50 50 60

350 350 350 350 500 500 2050

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COLLEGE SADHANA - Journal for Bloomers of Research,

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3. RESULTS AND DISCUSSION Preliminary Examination The Ion Trap Mobility Spectrometry (ITMS) is a portable instrument currently being used by the Malaysian Royal Police (PDRM) to conduct preliminary analysis for the detection of explosives and drugs in the spot itself (Fig 7). Preliminary analysis was conducted with ITMS in nearby “Chenderiang police station” and satisfactory results were obtained.

Examination in Laboratory, PJ, Selangor

Forensic

Science

No. 2,

FEBRUARY 2013

The post blast debris collected in the blasting exercises were analyzed in Forensic Science Laboratory using Thin Layer Chromatography (TLC), High Performance Liquid Chromatography (HPLC), Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), and Ion Chromatography (IC). Identification of High Explosives (HE) The post-blast explosion residues were separated into organic and inorganic extracts in the laboratory analysis. The result of analysis shown in Table 2 indicated that IED soil Nos. 3, 4, 5 and 7 contained high explosive. This was confirmed by HPLC analysis also. The retention time for control high explosive PETN is 8.965. The retention time for the soil samples IED Nos. 3,4,5,and 7 (shown in bold) are found close to the control value (Table 3) indicated the presence of high explosive. Also in the blasting site, pieces of electric detonators were collected in the explosion of IED No.3,4,5,and7. The electric detonators were used to trigger the high power explosives.

Table2: TLC analysis – Soil samples collected at the blasting point

Table 3: HPLC Analysis- soil samples collected at the blasting point

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T. Nataraja Moorthy, Reynold Vicente, Ariffin Bin Haron and Sivabalan Nagayah - Identification of Explosives in Improvised Explosive Device (IED) Explosions for use in Crime Scene Investigation

Identification of Low Explosive (LE) The soil samples of IED No. 1, 2 and 6 were subjected to qualitative and quantitative analysis sing ICP-OES and IC as per the standard procedure and presented in table 4 & 5. Table 4: ICP-OES Analysis, cations in control low explosive

Aluminum was detected in the analysis control LE because aluminum is present as fuel in low explosive. After the blast, the fuel was consumed completely and hence did not detect aluminum in the post blast sample. The soil samples were extracted with water and run in ion chromatography. Soil samples 1, 2 and 6 indicated the presence of NO3 - with other traces of impurities as found in the control LE also.

Table 5: ICP-OES findings of cation in soil samples in post blast (LE)

Table 6: IC Analysis – Findings of anions in soil samples and control low explosive

The quantity of NO3 present in soil samples indicated positively the presence of low explosives since low explosives contain nitrate compared to other anions like chloride, phosphate and sulfate. The presence of chloride, phosphate and sulfate may be ignored due to the fact that these ions are usually present in the soil crest. Based on ICP-OES and IC analysis, it was reconstructed that soil samples collected in the seat of explosion should have contained nitrates of potassium,

aluminum and magnesium, the ions that are present in low explosives like pyrotechnics used in fireworks. The instrumentation analysis confirmed that the IED No. 1, 2, and 6 are of low explosive (LE). We investigated a way to characterize the power of the improvised explosive device (IED) by comparing the fragments of pipe exploded in IED No. 2 and 3. The weight of these two pipe bombs were same i.e. 350g but IED pipe No. 2 was filled with low explosive 641

COLLEGE SADHANA - Journal for Bloomers of Research,

Vol. 5,

and IED pipe No.3 filled with high explosive. The high explosive filler produced a large number of pieces and smaller size pieces than the low explosive filler. This finding is in accordance with Oxley et al [9]. In IED No. 1 and 4 explosions, no fragments of either PVC or metal were recovered and thus ruled out the possibility of pipe bomb explosion. In all the blasting exercise, crater marks were formed. The presence of a crater is usually the most easily found indicator of an explosive’s use. Depending on the type, quantity and placement of explosives, the blast seat may be either diffuse or concentrated. Other types of explosions, such as dust or vapor explosions, do not cause craters or even have definitive blast seats. 4. CONCLUSION Bombs are the unique tool of a specific type of perpetrator, and investigation of bombings requires exceptional knowledge. The investigation of the bomb scene begins with an assessment of the incident to determine whether the scene exhibits evidence of an explosion and the type of explosion. Of the improvised explosive devices used in illegal activity, pipe bombs are a dominant configuration. The following observations were made in the IED blasting exercise. • Post blast debris collected at the seat of blasting yield more positive result in all IED blasting than debris collected in other places in the blasting site. Hence in a real crime situation, examination of the seat of blasting and collection of evidence is an important aspect to identify the nature and type of IED explosive.

No. 2,

ACKNOWLEDGEMENT The authors are thankful to Universiti Sains Malaysia for the encouragement to conduct this blasting research. Thanks are due to Royal Malaysian Police for providing explosive chemicals and their involvement in the blasting exercise. We wish to acknowledge the Director General, Chemistry department of Malaysia and Director of Forensic Science, Malaysia for the permission to conduct chemical and instrumental analysis in the forensic science laboratory. The project was designed for the forensic science students’ final year research project in partial fulfillment for the Bachelor of Science (Honors) in Forensic Science in Malaysia. REFERENCES [1]

Samuel Delvin, “Explosives”. 1st Edition, Sarup & Sons, Darya Ganj, New Delhi, (2000).

[2]

T.V.Narayanan, “Modern techniques of bomb detection and disposal”. 1st Edition, RA Security system, New Delhi, (1996).

[3]

Ayn Embar-Seddon and Allan D.Pass, “Forensics!” Pearson Education Upper Saddle River, New Jersey (2009).

[4]

Peter WS, “The evolution of Improvised Devices (IEDs)”. Armed Forces Journal. Brooking Institution Press, Washington. DC (2012).

[5]

Niamh ND, Max M. Houck, “Interpol‘s Forensic Science review”. Taylor & Francis, Boca naton, FL(2010).

[6]

Oxley JC, Smith JL, Resende E, Rogers E, Strobel RA, Bender EC, “Improvised explosive devices: pipe bombs”. J Forensic Sci 46 (3), (2001) 510–534.

[7]

Nataraja Moorthy T, Hidayatul Hazwani Binti Hamdan, Cheah Chaw Phang, “Identification of Fuel Oil in Absorbent and Non-absorbent Surfaces in a Site of Ammonium Nitrate-Fuel Oil (ANFO) Blast”. Malaysian Journal of Forensic Sciences, 3(1), (2012) 26-35.

[8]

Tan BK, “Urban geology of Kuala Lumpur and Ipoh, Malaysia”. IAEG 24, (2006) 1-7.

• The high explosive filler produced a large number of pieces and smaller size pieces than the low explosive filler. • Formation of crater mark in the explosion is an indication of involvement of devices (IED) and can also be used to quantify the explosive used for the blast. • The portable Ion Trap Mobility Spectrometry (ITMS) yielded more positive information in identifying the explosives in the spot preliminary analysis. 642

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