Investigators have identified a man they believe opened fire on two women, killing one, after a fender bender in San Francisco's South of Market neighborhood during the weekend.

Police are looking for Michael Sione Green, 23, for his role in the slaying of 23-year-old Melquiesha Warren of Oakland.

Warren had spent the night celebrating her wife's birthday at a nearby club when she and friend Danisha Bean, 21, of Hayward returned to their car just after 2 a.m. Saturday. Bean, the driver, accidentally rear-ended another car near Sixth and Jessie streets, police said.

A confrontation ensued, and a tall woman in a red dress approached their car and tried to open the driver's side door, police said.

Warren got out of the car in an effort to calm the woman when police said Green appeared with a gun. He fired at Warren and Bean, a bullet striking Warren in the head and another piercing Bean's side, police said.

They were transported to San Francisco General Hospital, where Warren died, six days short of her 24th birthday. Bean remains hospitalized with life-threatening injuries.

Green is 5-foot-11 and weighs about 230 pounds. He was last seen with a beard and long hair past his shoulders. He is possibly traveling in a 2001 Mercedes-Benz with license plate number 4UIP704.

Police consider Green extremely dangerous, and anyone who knows his whereabouts should call 911.

Police are still working to identify the woman in red, who was about 6 feet tall. Anyone with information should call the anonymous tip line at (415) 575-4444, or text a tip to TIP411 with "SFPD" on the subject line.