A gunman sprayed a suburban Milwaukee hotel with bullets Friday, killing his girlfriend and another person and wounding two others before holing up in his room with a hostage.

The man released the hostage unharmed after about half an hour of negotiations, Police Chief Thomas Bauer said. A suspect was in police custody, but Bauer did not give the man's name.

Two victims were taken to hospitals, and Bauer believed they were seriously injured.

Investigators believe the shooting started after the gunman had a fight with his girlfriend in their room at the Comfort Suites.

"After the suspect shot and killed her, he then went into the hallway where unfortunately people heard the noise, came out of their rooms, and one individual was executed," Bauer said.

The gunman then started firing down two hallways, and two other people were wounded by stray bullets, he said. "Dozens and dozens of shots were fired," Bauer said.

The gunman then grabbed another man as a hostage and called Milwaukee television station WITI, which transferred the call to police. After police arrived, the suspect indicated he had killed "some people," Bauer said.

Robin Martin, 41, of Forestville, said he awoke between 4:30 a.m. and 5 a.m. and opened his door on the third floor to investigate a noise.

"Half a dozen guys in SWAT outfits, automatic weapons and sidearms were in the hall. It scared the hell out of me," Martin said. "One of the men said, 'Sir, shut the door.' I did so immediately."

Police did not release the identities of the victims. The suspect was described as in his 30s and the girlfriend in her 20s, and both were believed to have lived in the Milwaukee area.