of some sort. and, deb, you just told us that they found casings backing that up. deb, are police still operating on the assumption that these three individuals escaped in a dark suv? or do they believe that one or more shooters may still be on site? >> well, what i had initially been told by a source according to witnesses who were questioned by police, these witnesses, multiple witnesses saw individuals dressed in some sort of darkish kind of clothing get into a black suv and pull out of the parking lot. that was the assumption they're working on. it's unclear whether anybody was in the building. i know a woman who had sort of said she thought that's what the working assumption was may have happened earlier. because now we're well into an hour that this has taken place. we do know that they are, again, you're looking at the bomb squad, the bomb technicians.