ISLAMABAD, Pakistan — On Sunday, a local politician named Mukarram Shah was in his car in the remote Pakistani village of Banjot when a bomb was detonated by remote control. He was instantly killed.
The bomb was made out of a pressure cooker, a common appliance in Pakistani kitchens and an increasingly common tool of terrorism in South Asia. It is the same sort of device that is believed to have been used in the Boston Marathon bombings, although authorities caution that it does not necessarily point to South Asian perpetrators; anyone could have taken advantage of easy-to-find online plans that have been posted by Al Qaeda, among others.
"We are defusing pressure cooker bombs almost daily," said Shafqat Malik, chief of the bomb disposal squad for the Pakistani province that includes the violence-racked city of Peshawar; the Swat Valley, where Shah was killed; and the militant-ridden tribal areas along the border with Afghanistan. "They're very common. Pressure cookers are one of the favorite IED containers for the terrorist groups."
IED stands for improvised explosive device, an appropriate designation for a bomb created out of one of the humblest of kitchen devices. Once common in American kitchens, pressure cookers have become relatively uncommon outside of immigrant communities in the U.S., but remain staples in Pakistan, India and surrounding countries, where they are prized for their ability to quickly cook beans and other long-simmering foods by using highly pressurized steam.
Because they have tight-fitting lids and are generally made of heavy metal, they create a powerful blast when filled with explosives and projectiles such as carpenter nails and ball bearings.
"Blast waves don't escape suddenly; the pressure builds up before the cooker gets broken," Malik said. "So the effect can be more lethal compared to other kinds of containers. The pieces of the cooker move outward like projectiles, hitting the target like a bullet."
Pakistani militants often detonate pressure cooker bombs by remote control — with a cellphone, for example — and usually bury the devices in the ground, Malik said.
Reports of pressure cookers being used as bombs go back to at least the 1990s, when Maoists used them against the Nepalese government during the 1996-2006 civil war in that country. By the 2000s, there were reports of their appearance in terrorist training camps along the volatile Pakistan-Afghanistan border. In 2010, the U.S. Department of Homeland Security warned that pressure cooker bombs were common in Afghanistan, Pakistan, India and Nepal and might be used in the United States.
"Because they are less common in the United States, the presence of a pressure cooker in an unusual location such as a building lobby or busy street corner should be treated as suspicious," the department said.
Since Malik began leading the bomb squad in Pakistan's Khyber-Pakhtunkhwa province in 2009, his officers have defused more than 5,000 explosive devices, about half of which have been pressure cooker bombs, he said. This year alone, his bomb disposal technicians have defused about 125 bombs in pressure cookers, he said.
The most recent prominent attack was the one that killed Shah, a member of the secular Awami National Party, which has supported operations against the Taliban in Pakistan's volatile northwest. The party has been rocked by a wave of terrorist attacks against its leaders and candidates running in the parliamentary elections scheduled for May 11.
In Afghanistan, where pressure cookers are also commonly used for bombs, a North Atlantic Treaty Organization patrol detonated one along a road two weeks ago, according to spokesman U.S. Army Maj. Adam N. Wojack. An Afghan Defense Ministry spokesman could not say how many of the 2,500 explosive devices detected and defused by Afghan forces last year were contained in pressure cookers, but said they were part of the mix of bombs, along with fertilizer bombs and those fashioned from rocket or mortar components.
The bombs have also been used extensively in India. In February, a pressure cooker bomb killed 17 people and wounded 119 in the Indian city of Hyderabad, according to forensic experts who determined that ammonium nitrate was the explosive substance used. One of the worst attacks occurred in July 2006, when seven pressure cooker bombs were planted beneath trains in Mumbai, killing more than 200 people.
Times staff writers Rodriguez reported from Islamabad and Magnier from New Delhi. Staff writer David Zucchino in Kabul, Afghanistan, and Tanvi Sharma of The Times' New Delhi bureau contributed to this report.