PHILADELPHIA (AP) – Police say a dispute on Facebook led to a shooting outside a Philadelphia high school that critically injured two men and wounded a 17-year-old girl.

Police Lt. John Walker says about 40 people, mostly teen girls, gathered for a fight outside Bartram High School on Thursday night.

Walker says rival groups of girls from different neighborhoods were involved in a conflict on Facebook before the shooting. At least 15 shots were fired from two handguns after the brawl started.

Walker is not elaborating on the exact nature of the dispute.