any of the scanner traffic? >> no, don, there is really still so much that we don't know. we're standing here at the corner of exitor and commonwealth. we have been seeing official vehicles come in. unmarked cars going in the perimeter. the fbi has taken over this investigation. they have set up a crime scene perimeter. there is a resource center set up for victims and their families for counseling. there is a whole lot we don't know still about these explosions. we don't know if this was a foreign or domestic attack. there were no early warnings before this attack. no credible threats is the word