Three people have died following a shooting at a Detroit barbershop known for gambling, police said. Several other people were wounded, and a reason for the gunfire wasn't known.

Shots erupted Wednesday evening outside Al's Barber Shop on the city's east side. Nine people were struck, including two men who were inside the shop and died, police said.

Sergeant Mike Woody said Thursday morning that a third person died at a hospital, but he didn't immediately have additional details. More information is expected to be released at a Thursday morning news conference.

"We're not sure if this was over a bad debt. We have no idea," Police Chief James Craig said earlier. "We know it's a barbershop and gambling has occurred in this location."

The number of people believed shot had gone back and forth between nine and 10 following the shooting, but Woody said Thursday morning it was nine after investigators determined one person wasn't involved.

Police said two cars pulled up and people inside the vehicles started shooting at each other.

"Somehow someone shot into the building, and that's when people rushed out of the building and were running into other area businesses for cover," police spokeswoman Kelly Miner said Wednesday night.

Craig said those who were shooting "engaged a couple of victims" before "several shots were fired." He said it's not known if any of the victims fired back.

Police were looking for at least two people believed to have carried out the shooting, Miner said.

Craig said they also were trying to locate two vehicles that they think the shooters might have been using: a 2004 white Chevrolet Impala that possibly has a broken window and bullet holes in the back, and a 2004 black Impala.

Lorne Carter told the Detroit Free Press that he was smoking a cigarette against the wall of a nearby business when he heard what sounded like 30 to 40 shots.

"It sounded rapid," Carter said.

The barbershop is in a strip mall along a major road. Nearby businesses include a Chinese restaurant, auto repair shops and a convenience store.

Miner said police were interviewing witnesses.

After the shooting, Elaine Williams waited behind yellow crime tape that police had used to cordon off several blocks around the scene. Her 29-year-old son had gone to the barbershop for a haircut, and she was frantic, The Detroit News reported.

"Help me find my son," Williams cried.