Mark Kerrigan's PTSD?

1994 Olympic silver medalist Nancy Kerrigan's brother Mark may have caused the fatal heart attack of their father Daniel Kerrigan. Mark has been described by his lawyer as an Army veteran with PTSD, possibly to explain his violent criminal history. But the only references to Mark's deployments have been he served in Egypt (possibly in the annual Operation Bright Star exercise) and didn't experience combat.

I don't understand: if Mark Kerrigan wasn't in combat, then how did he develop PTSD? Serving overseas as a soldier in a non-combat deployment doesn't cause PTSD. Maybe he developed PTSD in prison, instead?

Update 20FEB10: I heard that Kerrigan's PTSD may be related to the famous 1985 tragedy where 248 members of the 101st Airborne died in a plane crash returning from duty in Egypt. Supposedly, Kerrigan was meant to be on the flight, but didn't take it for some reason, and the near-brush with death and the deaths of his comrades traumatized him. Certainly, surviving such an event can be traumatic, but does it qualify as PTSD?

Eric