An 18-year-old woman in Prince William County was slightly wounded by gunfire Friday night, capping an evening of mayhem following a basketball game at Gar-Field High School, police said.

Police said a large fight broke out at the school after the game, and officers dispersed several unruly crowds of young people, with no injuries reported. However, some of the juveniles involved in the disturbance reassembled at Potomac Mills Mall, and police were summoned there.

No one was injured or arrested at the mall, police said. But the combatants encountered one another again shortly after 10:30 p.m. near Old Triangle Road and Heth Court in Dumfries. In the fight that broke out there, someone fired several shots from a handgun.

Although no one was injured in that incident, the assailant apparently fired several more shots a short while later, at Old Triangle Road and Sigel Court, police said. The 18-year-old victim — a pedestrian who had not been involved in the earlier disturbances — was taken to a hospital with a minor wound after a bullet grazed her head.

Police said they have obtained an arrest warrant for the alleged gunman and were trying to locate him.

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