GOLDEN, Colo. (AP) — Law officers are searching for a gunman after shooting erupted outside a suburban Denver concert that left three people wounded.

Jefferson County Sheriff's spokesman Mark Techmeyer said Red Rocks Amphitheater was shut down after the shooting in the parking lot about 10:30 p.m. Thursday as the concert was ending,

The three wounded traveled by car into nearby Denver where they were located by police and taken to a hospital.

Techmeyer said the gunshot wounds did not appear to be life-threatening, but he had no other information on the injured.

He said authorities were looking for a black male with a rifle.

Thousands of people were at the concert and all cars were searched as they left.

The Denver Post said Nas, Schoolboy Q and Flying Lotus performed at Red Rocks Thursday night.