http://www.msnbc.com/news/676895.asp
IMPROVISED EXPLOSIVE
       FBI agent Margaret Cronin testified Friday about the explosives, saying preliminary tests on Reid’s sneakers showed the presence of triacetone triperoxide, or TATP.
       The substance can be manufactured from common chemicals such as acetone, peroxide and acid — and it has emerged in recent years as an improvised explosive for terrorist bombs, even though it is notoriously difficult to handle. TATP, sometimes referred to as “The Mother of Satan,” was used in last summer’s Tel Aviv disco bombing in which 21 people died.
       Tests also turned up the presence of another high-explosive chemical called pentaerythritol tetranitrate, or PETN, U.S. officials told NBC News on condition of anonymity.
       PETN is commercially available in blasting caps and detonator cords, and is useful for construction and military applications. But the substance can also be separated from such commercial products to create deadly plastic explosives, and terrorists have used it in that way for decades. PETN is a key ingredient in the Czech-made Semtex plastic explosive, which brought down Pan Am Flight 103 in 1988, killing 270 people.
       Agence France-Presse reported Friday that Reid told the FBI he bought $1,500 worth of PETN explosive in Amsterdam. The report was attributed to unnamed French officials familiar with the investigation.
       Reid was said to have found the sellers over the Internet, Agence France-Presse reported. The news agency said the FBI was contacting police in Belgium, France and the Netherlands to inform them of the Web danger, but an FBI spokeswoman in Washington denied that aspect of the report.
       “We have not done that,” she told MSNBC.com on condition of anonymity.
       U.S. officials told NBC News that the TATP would have served as the bomb’s detonator, and the PETN would have been the main charge. The PETN was mixed with petroleum jelly to form a putty-like substance, the officials said.