The bombs believed to have been used in Monday's Boston Marathon attack used pressure cookers, an element that was also used in the failed 2010 Times Square bombing attempt.
According to NBC News, Monday's bombs were capable of propelling shrapnel and fragments at speeds of up to 3,300 feet per second, more than three times the speed of a 9 mm round fired from a pistol.
The three fatalities and injuries suffered by the more than 100 wounded in Boston were largely caused by fragments of the bomb's casing, and the ball bearings and BBs packed around the explosive, along with other debris propelled through the air by the explosion, according to NBC News.
In the May 1, 2010 attempted bombing in Times Square, a pressure cooker packed with fireworks was used as a primary charge, placed inside a gun locker in the bomber's vehicle, with the locker containing the main charge. The pressure cooker worked as intended, but the bomb did not go off.
The bomb was discovered when a street vendor alerted police after he noticed smoke coming from the parked SUV. Faisal Shahzad, who authorities said was backed by the Pakistani Taliban, was arrested for the bombing attempt and sentenced to life in prison after pleading guilty in court.
Bombs made with pressure cookers were also used in a series of attacks in Mumbai, India in 2006. In those attacks, seven pressure cookers with mixtures of RDX and ammonium nitrate were placed on trains, killing more than 200 people.