Two young men were killed and four women were injured, one critically, after a gunman opened fire early Sunday in a West Oakland warehouse that had been converted into an unlicensed music club, police said.

The shots rang out at 2:45 a.m. after a CD release party in a building of corrugated metal that has no sign but is known as The Ware House, at 34th and Chestnut streets near the California Hotel.

Guests at the event - which was scheduled to run from 10 p.m. to 2 a.m. and had been publicized on flyers and the Internet - celebrated a CD by Oakland hip-hop artist Zulu the King.

The performer, otherwise known as Xavier Lowery, said the release party ended peacefully and he left the warehouse to get something to eat. By the time he returned to socialize, he said, the assault had happened.

"I feel bad for the families," said Lowery, 28. "How do these mothers feel when their child is not coming to see them for Mother's Day? It's these senseless acts of violence we don't need."

Oakland police said a 19-year-old man from Oakland and a 24-year-old man from Modesto were pronounced dead at the scene by paramedics. None of the victims has been identified.

A 36-year-old woman was taken by ambulance to Highland Hospital in Oakland in critical condition, said Officer Holly Joshi, a police spokeswoman. She said three other female victims, two who are 20 and one who is 21, transported themselves to the hospital and are expected to survive.

Police have not released any details about the suspect or suspects or determined a motive for the shooting. While saying the venue was unlicensed, she said she did not know if anyone affiliated with it would face punishment.

Efforts to reach the building owner were unsuccessful.

Adam Ivey, a jazz musician who rents studio space in the building, was in another room when he heard shots fired and described the ensuing scene as pandemonium.

"I don't know exactly what went bad but I heard stories about it being a turf war," said Ivey, 29, of San Leandro. "I've never experienced anything like this firsthand."

Ivey said the warehouse had the potential to be a gathering place for people in the neighborhood to play and learn music. Recently, he said, the facility hosted a birthday party for a 13-year-old boy.

"When you try to do something positive and you get this kind of result, it's really sickening," he said.

Anyone with information about the shooting is asked to call the Oakland police homicide section at (510) 238-3821.