According to witnesses aboard a BART train headed to San Francisco on Saturday night just before 8 p.m., right before the doors would open at the West Oakland Station, a "disheveled looking man" shot and killed a passenger sitting next to the door.

The suspect, who may have boarded at Rockridge or MacArthur station and is now being described to the Chronicle as a black, bald, 6-foot-3-inch man wearing a green jacket, military-style boots, and a backpack, fled on foot.

“Officers responded and found a subject dead at the scene,” said BART police Lieutenant Kevin Franklin, adding that the victim was shot multiple times.

"Everyone just got down on the ground," said one witness. "People were screaming. It was chaos."

Another witness administered CPR to the victim, noticing that he held a knife.

KQED notes that BART detectives have yet to determine a motive for the shooting but do not consider it to have been random. Currently, they're reviewing surveillance footage taken inside the train. Correction: ABC7 updates us that although BART train cars have cameras inside them, not all record video. "To get the recordings," said one official, "we have to take trains out of service and detach the recordings from underneath the train in order to get to them for investigative review."

Last, an added complicating factor is that the coroner's office has been unable to as yet identify the victim.

Previously: Man Shot And Killed On BART At West Oakland Station