Never heard of it happening before, however I knew a Fire Capt. who had received a Silver Star for hand to hand action in Vietnam, who would on rare occasions have flashbacks chasing fellow firefighters around the station in his sleep thinking he was being overrun by Viet Cong.
We would come in at shift change on more than one occasion and find one of the guys with bruises starting and a goose egg on his head and say what's up? "Oh, Don had a bad night last night." I felt sorry for those guys, but they all took it in stride.
Good thing he didn't bring any firearms to work with him.