The pressure cooker bombs that exploded at the Boston Marathon have been widely used by terrorists. (Source: Homeland Security)
(RNN) - The kind of homemade bomb used at the Boston Marathon has been used by terrorists in India, Pakistan, Afghanistan and Nepal according to an unclassified document released by Homeland Security in 2010.
That same year, instructions on how to construct the bombs were published in an online magazine with Al-Qaeda ties.
A simple Google search also reveals multiple websites with information on how to build and detonate such a bomb.
The Homeland Security document warned the bombs were portable and easy to transport and conceal.
"Terrorists can exploit the innocuous appearance of easily transportable items such as pressure cookers to conceal IED components. Placed carefully, such devices provide little or no indication of an impending attack," the document said.
Similar bombs were used in the Mumbai train explosions that killed about 200 people in 2006. The same sorts of bombs were used in the 2010 attacks on Times Square and on World Vision International in Pakistan.
In Boston, investigators found a circuit board that they think may have triggered the bomb, according to the Boston Globe. CNN has said a timer set the bomb off and it was unlikely that a cell phone was used.
The Associated Press said a person briefed on the probe said 6-liter pressure cookers filled with ball bearings and metal was hidden inside duffel bags.
Copyright 2013 Raycom News Network. All rights reserved.