The soldier who accidentally shot and killed fellow soldier Or Hadad of the Golani Brigade on Thursday night was arrested over the weekend on suspicion that the discharge took place when he was playing with his weapon. Hadad, a 20-year-old sergeant from Beit Dagan, was shot in the back Thursday night during a training exercise in the Golan Heights. The army said that Hadad was accidentally shot by a fellow soldier while the two were in separate tents in the base. He was airlifted to Sieff Hospital in Safed in critical condition, and succumbed later to his wounds. Hadad was buried on Friday afternoon at the Rishon Lezion Military Cemetery. Military Police are investigating the possibility that the soldier fired the shot accidentally while cleaning his weapon or, in the more grievous scenario, that he was playing with his weapon. "If it was a game, then it's negligence, and if the bullet was left in the gun following an exercise, then it's also negligence," former OC Central Command Maj.-Gen. (res.) Yair Naveh told Army Radio. "If we've gone back to games with guns, we're in a much more severe situation." The shooting was the second fatal accident in the IDF last week. Last Wednesday, St.-Sgt. Uriel Peretz Liwerant was killed when his tank overturned while crossing a portable bridge during a drill in the Golan. Jerusalem Post Staff contributed to the report.