Beware, the following video is quite disturbing, at least from minute 03:50.
It shows the fatal incident occurred to a Thai paratrooper whose chute gets caught on plane while other military safely jump. The doomed soldier remains hooked to the plane for about 3 minutes, before straps fail and he falls into the ground without managing to open a reserve chute.
The plane can be seen turning (most probably returning to the homebase) at a lower speed, but it does not seem to climb to give the soldier enough clearance to open the emergency parachute (if any).
Few days ago a potentially tragic midair collision left 11 people (9 skydivers and 2 pilots) miraculously unhurt. In this case, the Thai paratrooper was not as lucky.