I would agree that detonation by the runners doesn't make as much sense as doing it in the crowd or by cell phone. I'm wondering though, if what we're seeing is a distraction to put people or items in place? It does seem really odd that this old guy caught an object, apparently thrown by the woman in green (although it might just look like that on film), and no one asked him what he caught. Maybe it was a whole set of signals to get people placed.

What attracted me the most to this video, frankly, was the apparent attempt to suppress it. That always makes me suspicious and thinking that we should look closer at something.