Police use tear gas to disperse protest over police shooting of an unarmed man.
In grainy cell-phone videos played over and over on the Internet, police officers force an unarmed black man to the ground and hold him face-down on a crowded train platform. Suddenly one of the officers draws his gun and fatally shoots the man in the back — then looks up.
The New Year's Day death of 22-year-old Oscar Grant has led to violent street protests amid allegations from the family's attorney that some of the officers used racial slurs.
The officer remains free and has not been charged with any wrongdoing. And some experts have questioned whether he fired his gun deliberately or mistakenly believed he was using his stun gun instead.
At a rally Wednesday attended by hundreds of people, Shawanda Thomas held a fluorescent yellow sign that read: "Oscar Grant: Murdered! The Whole Damn System is Guilty."
Extra police were posted Thursday at Bay Area Rapid Transit stations after a group of angry demonstrators smashed storefronts late Wednesday, set fire to cars and clashed with officers equipped with riot gear and tear gas in downtown Oakland. More than 100 people were arrested and about 300 businesses were damaged.
Oakland Mayor Ron Dellums called for calm. "Even with our anger and our pain, let's still address each other with a degree of civility and calmness and not make this tragedy an excuse to engage in violence," he said. "I don't want anybody hurt. I don't want anybody killed."
At the mayor's request, the Oakland Police Department launched an investigation into the shooting Thursday. Alameda County District Attorney Tom Orloff, whose office also is investigating, said he probably would decide within two weeks whether to file charges.
Transit police officer Johannes Mehserle was initially placed on paid leave. He resigned from the BART police force Wednesday, but officials say he has refused to speak with the transit agency's investigators. He has not spoken publicly about the incident.
Mehserle's attorney, Christopher Miller, declined to comment on the investigations.
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