if you ever witness an explosion close by, and you are not seriously injured and about to run away - DON"T
Bombs/terror acts like that become more and more planned to targeted as many people as possible in following way
there will be a small initial charge that goes off and creates panic- the crowd will go nuts and trample towards another direction - where the second or third charge goes off - creating a multiple of casulties.
this is what insurgency is doing the last 8-10 years and its become a wide spread tactic in a large scale attack
so if s*** hits the ground and your ok and safe from secondary explosions of cars - stay where u are as close as possible to the ground and not infront or underneath window glass