CNN

SAN FRANCISCO — Police are bracing for riots in Oakland, California as a verdict nears in a racially-charged murder trial of a white former police officer accused of killing an unarmed black man.

On the Oakland Police Department website there are messages from the police chief and Oakland's mayor warning people to stay calm.

"We anticipate that regardless of the verdict reached by the jury, demonstrations could occur in downtown Oakland, and potentially throughout the city," one of the messages said. "We will not tolerate destruction or violence. We live here, and we love Oakland. We understand that the community is grieving, and we are in this together. We will get through this together."

Closing arguments are scheduled to conclude Friday in the murder trial of former Bay Area Rapid Transit police officer Johannes Mehserle, said CNN affiliate KTVU reported.

The jury could begin deliberating late Friday. Mehserle could be found not guilty, guilty of murder or guilty of a lesser offense like manslaughter.

Mehserle is accused of fatally shooting an unarmed man on a California train platform on New Year's Day last year.

Mehserle, who is white, has pleaded not guilty to killing Oscar Grant III, a 22-year-old black man.

The shooting was captured on a bystander's cell-phone video camera, widely circulated on the Internet and on news broadcasts, and it spurred several protests and riots in and around Oakland.

The trial has been moved from Alameda County to Los Angeles due to pre-trial publicity.

Bay Area Rapid Transit police were called to Oakland's Fruitvale station January 1, 2009, after passengers complained about fights on a train. Officers pulled several men, including Grant, off the train when it arrived at Fruitvale.

The video showed Mehserle pulling his gun and fatally shooting Grant in the back as another officer kneeled on the unarmed Grant. Mehserle has said at the trial that he intended to draw and fire his Taser rather than his gun, KTVU reported.

Mehserle resigned his position a few days after the incident and was later arrested in Nevada. Mehserle was released on a $3 million bond.

Grant's family filed a $50 million wrongful death lawsuit against the officers involved in the incident.

In January, the transit system agreed to pay $1.5 million to settle the suit. The money will provide financial support to Grant's young daughter.

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