Q&A: Pressure cooker bombs
- Published
Twisted metal recovered at the Boston bomb scene suggests the use of a pressure cooker bomb
Early investigations into the deadly attack on the Boston Marathon suggest that the two bombs were placed in pressure cookers.
The vessel has long been favoured by bomb-makers in Afghanistan because it can be rigged into a cheap but murderously effective anti-personnel device.
What are the advantages of a pressure cooker for a bomber?
How common is its use as a bomb?
Pressure cooker bombs
Pressure cookers are cheap and easy to buy. Details of a pressure cooker bomb were once published in an online al-Qaeda magazine. It was one of three devices used in the 2010 attempted Times Square attack.
The US Dept of Homeland Security has issued two previous warnings about the dangers of pressure cooker bombs. The cooker is a tightly-sealed pot, which can increase the force of the blast when packed with explosives.
The explosion can be triggered using a simple device like a digital watch or mobile phone.
The Boston explosions contained metal shards, nails and other types of shrapnel, designed to cause maximum injury. Many of those wounded in the Boston attack suffered lower leg injuries and shrapnel wounds.
Who do the bombers target with such devices?
Were pressure cooker bombs used in the US before Boston?
What do we know about the Boston bombs specifically?
Are pressure cooker bombs associated with particular militant groups?