BERKELEY, Calif. -- Hundreds of people marched through Berkeley for a third night a row, blocking a major highway and stopping a train as activists in this ultra-liberal bastion protested grand jury decisions not to indict white police officers in the deaths of two unarmed black men.
Demonstrators blocked traffic on both sides of Interstate 80 in Berkeley, while another group stood on and sat on train tracks, forcing an Amtrak train to stop Monday night.
At one point, a woman in a vehicle stuck in the traffic jam caused by the I-80 blockage went into labor, and the local fire department had to get her to a hospital.
The city's mayor called some of the protesters "cowards and thugs."
A large group of people began peacefully marching earlier Monday through downtown Berkeley. The first stop for demonstrators shouting, "Who do you protect? Peaceful protest" was the Berkeley Police Department. A line of officers in riot gear blocked them from getting close to the building. The group then headed to a Bay Area Rapid Transit train station and sat outside, prompting authorities to briefly shut down the station.
But as the night went on, the protesters divided into smaller groups that disrupted traffic and train passengers.
The California Highway Patrol said in a tweet that some in the crowd tore down fencing to enter the freeway.
By 10:15 p.m. local time, protesters were being cleared from both directions of the freeway but traffic was still backed up, reports CBS San Francisco station KPIX-TV, citing the California Highway Patrol.
Merchants in downtown Berkeley on Monday cleaned up broken glass and took stock of the previous night's looting after a protest turned that turned violent Sunday night.
Although many activists in other parts of the country have gone home, protests in Berkeley and Oakland are still active, reflecting the area's long history of protest dating to the 1960s.
The crowds that came out to protest in Berkeley numbered only a few hundred, but some are not college students or residents so much as full-time demonstrators who protest anything - war, prison conditions and economic inequality - and sometimes use demonstrations as a pretext for violence and vandalism, just as they did during the Occupy Wall Street movement.
Berkeley Mayor Tom Bates said a tiny fraction of protesters are obscuring the wider message calling for reform of policing policies nationwide.
"The people in the Bay Area are sensitive to worldwide issues," Bates said. "Unfortunately, there is a small element that uses violence at times to make their point."
Bates called the violent elements of the demonstration "cowards and thugs who need to take off their masks."
It was not immediately known if protesters were arrested Monday night. Five people were arrested Sunday, police said.
Stuart Geiger, 27, a University of California, Berkeley, doctoral student, attended the protest and recorded video of peaceful demonstrators attempting to stop the looting of a Radio Shack.
"There was a pretty vocal sentiment there about keep this a peaceful protest and stay on message," Geiger said.
Another peaceful protester was struck by a hammer and slightly injured when he tried to stop looting.
In keeping with the city's protest history, Berkeley leaders have put limits on their police. Officers cannot have search dogs, stun guns or helicopters and are restricted in the type of gear they can wear, said Berkeley police union President Sgt. Chris Stines.
"All of us are out there wearing what we wear on patrol, and as a result, we are getting pretty banged up," he said, explaining that shin and chest guards and padded vests would help prevent injuries. At least three officers suffered minor injuries.
The protests started after a Nov. 24 decision by the grand jury not to indict officer Darren Wilson not to indict officer Darren Wilson in the killing of Michael Brown in Ferguson, Missouri. A New York grand jury on Dec. 3 declined to prosecute a police officer captured on video applying a fatal chokehold on Eric Garner. That decision set off another series of demonstrations nationwide.
Oakland police have arrested about 200 people since the protests started.