At 7:30 p.m. Friday, about a hundred protesters found themselves pinned down at 6th Avenue near 17th Street in Oakland. One protest organizer, Rachael Jackson, shouted: "Call the police! Tell them we're being held hostage!"

The cry was a note of weary sarcasm hours after the sentencing of former BART police officer Johannes Mehserle. It was the police, of course, who had the protesters surrounded.

As Jackson puffed on a cigarette, lights from the TV crews that had followed the protesters on an aimless march shined off the helmets of officers wearing riot gear.

After circumnavigating barricades, and tearing down fences, and smashing car windows, and trudging through dark parks with the police in pursuit, the protest ended here in a residential neighborhood, where the police closed in and made dozens of arrests.

Earlier in the day, Mehserle, who shot and killed an unarmed black man, Oscar Grant, on the platform of the Fruitvale BART station just after New Year's 2009, was sentenced by a Los Angeles Superior Court judge to two years in prison for involuntary manslaughter. With time served, Mehserle is likely to spend little more than a year in prison.

The march was the exhausted conclusion to the tumultuous events that have consumed Oakland, including the unrest that followed the end of Mehserle's trial in July.

In the afternoon, after the light sentence was handed down, a few hundred people gathered for a rally in front of Oakland City Hall. Poets, rappers and activists shared the stage to spread a message about the need for social change.

The gathering was smaller than the one in July and lacked the same urgency. The long ordeal seemed to have taken a toll.

“I’m exhausted. Just exhausted,” said Nicole Lee, the executive director of the Urban Peace Movement, a nonprofit violence prevention organization, as she cradled a large cup of coffee at the rally.

"The real question is: What does justice really look like?" she said. "Even if one officer gets many, many years. Is that justice? Justice to me looks like young people who aren’t afraid to walk down the block without getting shot.”

The plan after the rally, agreed upon by activists, city officials and community-organized “peacemakers,” was simple: the crowd would disperse to DeFremery Park for a memorial.

Instead, at about 6:30 p.m. a splinter group of protesters led about 100 of those gathered in Frank Ogawa Plaza and began a 3.5-mile march to the Fruitvale BART station, where Grant was killed.

The marchers filled the intersection of 14th Street and Broadway, blocking traffic, and doubled back, where they were met by several lines of police officers gripping batons. As some of the more aggressive protesters inched forward, police inched back, and the protesters resumed the march up the middle of 14th Street. Police followed in cars.

The march picked up speed, continuing onto Oak and up 10th Street, where another phalanx of officers blocked the street. Several protesters tore down a fence and the crowd rushed down a dirt path through Peralta Park onto 11th Street.

They quickly evaded more officers by veering left onto 1st Avenue past Lake Merritt.

Along the way, some dissension began to occur within the protesters’ ranks. While most urged peace, a few protesters began to shatter car windows and storefronts. Some police were pelted with rocks, and one officer’s gun and holster was torn off. Police also say an officer was hit by a car. By the time the crowd reached 6th Avenue and 18th Street, the sudden massive approach of police officers caused chaos and fear as some organizers worked to regain control of the mob. The majority of the protesters were not violent.

“We about to get whuped up,” said one young organizer to a woman leading the crowd with a bullhorn. “I wanna organize us to leave without getting our asses whuped. Peaceful, please.”

The crowd united, chanting, “If we leave, we’re leaving together.” But police closed. A line of officers along 17th began moving forward. 

“They’re squeezing us,” said Aislyn Colgan, an EMT and street artist. “This is bullshit. There are literally hundreds of police on both sides of us.”

One officer announced over a bullhorn that the march was illegal and ordered everyone to disperse. But in the confusion, many in the crowd could not hear the orders and found nowhere space to escape.

“Let us leave!” Colgan and others shouted.

Police began to make arrests. More than 150 protesters were detained with zip ties on the ground as police prepared to bus them to Alameda County Jail. Some were arrested at the Fruitvale station, and some downtown.

By 8:30 p.m., the protest was over.