FORENSICS
examination. British WITs uncovered characteristic IRA bomb-maker techniques. Electronic components could be traced to a specific large company; another attached taunting messages to his fabricated IED containers; another built bombs with ‘spaghetti’ wiring. Exploitation To exploit a device, components are triaged: unsafe explosive items are removed and the rest go off to forensics. Even after suicide bombings grisly process of collecting forensic evidence can lead to sources and bring about convictions. Photographing bomb components is very important as evidence such as tape used to connect electrical components may be altered during subsequent forensics. It also aids IED reconstruction. Advanced sampling equipment can identify chemical components found on surfaces. Detonation of high-explosives leaves signatures on nearby objects as embedded soot, distinct discoloration and knife-like edges on metallic surfaces. A specimen can meet specific criteria – such as a brand-name 9 V battery. DNA and fingerprinting DNA and fingerprint testing identifies known miscreants. Repeat configurations can point to a single perpetrator. Components like tape must be fingerprinted before removal from a device; debris from surroundings post-blast is also examined.
● George Soros received the first of 14 bombs at his home in Katonah, New York in October 2018 ● Suspect in Plantation, Fla had made “roughly six inches of PVC pipe, a small clock, a battery, some wiring and energetic material” sent to senators and former presidents ● A single fingerprint and small amount of DNA tracked down a suspect with long arrest history ● A fingerprint found on the envelope of a bomb intended for a Republican politican and a small amount of DNA was discovered on two other packages It has dealt with major terrorist incidents including London 7/7 2005 and Manchester Arena May 2017. Material is examined at Fort Halstead – whole vehicles, doors, and even parts of Hammersmith Bridge, which the IRA tried to blow up three times. FEL’s work is split into four main categories: ● post-explosion scenes ● improvised explosive devices ● finds and caches of explosives and related materials, and ● examination of suspects, property or premises for trace levels of explosives (that is, amounts that cannot be seen by the naked eye, as opposed to bulk levels, which can be seen, handled and weighed) The appearance is assessed, whether a powder or fragments from blown-up debris. Burning a powder first reveals whether a material is
energetic. Black powder – a component of gunpowder – has a sulphur egg odour. A lilac flame colour emits from potassium (nitrate). Spectroscopy and chromatography detects the smallest quantities of explosives. Scanning electron microscopes have an energy dispersive spectrometer to identify the potassium and sulphur and the carbon present from charcoal. Ion chromatography confirms the presence of nitrate and potassium. MAYBE THEY HAVE A CAMPING STOVE, OR A HOME BREWING HOBBY, OR THERE IS A HAIRDRESSER LIVING AT THE PROPERTY. BUT THEY’RE ALSO THE THREE PRECURSOR CHEMICALS FOR THE MANUFACTURE OF HMTD. FEL SENIOR FORENSIC SCIENTIST Police on Parsons Green, west London following the attempted bombing on a tube train in September 2017. The partial detonation greatly aided forensics.
TEN YEARS AGO, IT REQUIRED A SPOT OF BLOOD THE SIZE OF A QUARTER, BUT NOW WE CAN DO IT WITH A HEAD OF A PIN. THAT’S MADE TOUCH DNA A LOT MORE POSITIVE. DR. PETER STOUT, PRESIDENT OF HOUSTON FORENSIC SCIENCE CENTER
Dstl FEL The Dstl Forensic Explosives Laboratory (FEL) is the world’s premier specialist explosives lab.
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XPLOSIVE
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