it's still unclear whether the suicide bomber managed to get in. but the timing of the bombing, if it was a suicide bomber, someone setting it off on purpose, if that's the scenario, it appears to be someone setting it off as people were e leaving the arena. the concert we're told by many witnesses was just ending and people were starting to stream out and that's when the explosion happened. and the authorities here have been told by british authorities that that a large number of the casualties were caused by the crush of people, the stampede of people trying to get out of the arena, the witnesses say, of course, they didn't know where the explosion happened. they couldn't see it, many of them, if in fact it was in this foyer area. some reported hearing an explosion. those were the people who were outside in that area where the suicide bomber was.