Pressure cooker may hold key to solving blast

In kitchens, they prepare food faster, but pressure cookers by their very nature help make good bombs, amplifying the blast and the carnage.

They don’t just hold the explosives. The tightly sealed pot makes easier-to-obtain but weaker explosives faster and stronger. And they may also help investigators find out who built the deadly homemade bombs that exploded at the Boston Marathon on Monday.

Investigators found fragments of ball bearings and nails, possibly contained in a pressure cooker, said Richard DesLauriers, the FBI agent in charge in Boston. He said the items were sent for analysis.