a soldier, nazir abdul, convicted last year of plotting an attack at ft. hood, texas, was using a bomb-making recipe from an al qaeda-linked online magazine that used a pressure cooker. in july of 2006, more than 130 died in a series of attacks on the mumbai transit system with pressure cooker explosives placed on the trains. the department of homeland security has warned of the potential terrorist use of pressure cookers saying "as a common cooking utensil, the pressure cooker is often overlooked when searching vehicles, residences, or merchandise crossing the u.s. borders." now, of course, there's still much more that authorities want to know about this particular case. and for the very latest on the investigation, we're joined now by nbc news justice correspondent pete williams from washington. so, pete, the very latest on the pressure cooker scenario that you're hearing? >> right. as you say, used for decades in terms of building bombs, so that's not going to be an area of inquiry that will immediately lead them in a certain direction, because the inst