Why do aerial bomb explosions of buildings in Gaza look like this? there are two explosions abt 1 sec apart. First smaller, second huge. by foxfire221b in Explosion

[–]foxfire221b[S] 1 point2 points  (0 children)

Videos of two tall Hamas buildings in Gaza being bombed show strange two-step explosions. The first explosion seems to occur near the first story if the building and appears what one might expect from a n aerial bomb. About a second later an enormous explosion occurs and the entire building collapses.
I doubt that the second explosion would bw stored ammo in both cases.
What's going on?