here is a theory that i heard.
1) pilots decompressed the cabin
2)pilots wear masks but all passengers die
3)pilots turn around and safely land in a remote area
4)pilots destroy black box
5) pilots are waiting with plane for plans to be finalised
6)plans to attack israel using the plane.
in short: this was the only way to get a plane (by killing 237 people) in order to make an attack on israel.
i dont know what they have done with all the bodies if this theory is true.
it is not my theory.