oscar-grant.jpgOAKLAND, Calif. (AP) _ Oakland police are preparing for possible violent protests after jurors reach a verdict in the trial of a former Bay Area Rapid Transit police officer accused of fatally shooting an unarmed black man on a station platform.

Police on Friday, June 18 simulated a riot at the Port of Oakland in which plainclothes officers posed as protesters and threw objects at other officers.

Oakland police spokeswoman Holly Joshi says the shooting of 22-year-old Oscar Grant on New Year's Day 2009 has raised tension in the city. Johannes Mehserle, the officer accused of killing Grant, is white. He has pleaded not guilty to murder.

Police want to prevent the type of violence that rocked Oakland days after the shooting, when rioters smashed storefronts and set cars on fire.

Pictured above is Oscar Grant.