reporter: 24 hours after this event, erin, we don t have a possible description of a suspect, a car a motive, anybody claiming responsibility. it really was stunning to hear and see all those law enforcement officers basically asking for the public s help in trying to solve this. they are working hard, they re trying to piece together the bomb, the fragments, the residue, etc., all taken to quantico, trying to re-enact the bomb, that s kind of standard procedure and also they mentioned the pressure cook never one of the black nylon bags, then a possible pressure cooker was as strong as they could determine that to be. drew griffin, thank you very much. certainly amazing, kind of brings back to me, i remember talking to former press secretary leon panetta who said his biggest fear was a lone wolf attack would be the hardest thing to track and that s what