closely. somebody may know the people because they passed by some sort of a store they attended some sort of an event. and so the hats are very telling. now it may be that these guys are trying to throw investigators off. but at the same time, you know, this has been planned so carefully. and every detail is a chance. but that s one of the things that investigators are very, very interested in trying to find out where the face is and where the hats r so every small thing is a clue. this may sound a bit naive, in fact, the bib bib gfbi gamble m paid off and some calls are coming in. we have to hope. thank you, deb. we have much more on the images as we go frame by frame of the two men that the fbi is calling suspects. our guest is an expert on analyzing these types of images. he s going to tell us how to spot clues that may not be obvious to any of us watching, the untrained eye. next, we re going to go to texas for the latest on last night s horrific explosion at a