Except for the burning coverall leg, this is entirely speculation. The Israelis have some darn good snipers, and these guys could all easily have fallen to one or more of them. As we saw on the thread yesterday, they are perfectly capable of a neck shot from a goodly distance away. A head is even easier, especialy on a target that isn't moving around much, as the guy with out a coverall, with camo pants and the white checkered headgear was that took the neck shot.
But you know what? I don't really care how it went down. The Israelies know how the Pali's treat their troops if they capture them, they kill them in as bloody a manner as possible, then show off their own blood stained hands to the crowd.