McCaul, a former federal prosecutor who received briefings Tuesday morning from the FBI and Homeland Security officials, also said that authorities still did not know whether the attack was a foreign or domestic plot.
An explosive device fashioned from a pressure cooker was also used in the attempted bombing of Times Square in New York in 2010, the Times noted.
A USA Today report citing an unnamed source said that the explosives were put in six-litre pressure cookers, placed in black duffel bags and left on the ground. They were packed with shrapnel.
