Martinsville, Ind. ? Dustin Tatum was leaving his middle school cafeteria Friday when he heard a loud bang, then chaos ensued as a teacher rushed him and several fellow students into a classroom, locked the door, turned off the lights and ordered everyone to hit the floor.

Only later did Tatum learn his close friend, a 15-year-old classmate, was shot in the stomach and that police were identifying the alleged shooter as a former student expelled from the central Indiana school just days earlier.

“It was a nightmare hearing my friend just got shot and he’s being lifelined to the hospital,” said Tatum, 14.

The lone victim, Chance Jackson, was listed in critical but stable condition Friday evening at Methodist Hospital in Indianapolis, where he was taken by helicopter.

The former 15-year-old student suspected in the attack was arrested miles away on the south side of Martinsville about an hour after the shooting, which unfolded before 7 a.m. Friday, just as classes were about to begin, State Police Sgt. Curt Durnil said.

The teen was being questioned at the county jail as Morgan County prosecutors reviewed possible charges against him.