An officer was briefly hospitalized after being assaulted during a mostly peaceful protest in Northern California over the fatal police shooting of an unarmed teen in Ferguson, Missouri, authorities said Saturday.
Officers demonstrated "a high level of restraint" during Friday's protest, said Sean Whent, chief of police in Oakland, a city that has grappled with numerous protests spanning from the fatal shooting of Oscar Grant by a transit police officer in 2009 to Occupy Oakland in 2011-12.
Another Ferguson-related protest was planned in Oakland Saturday evening.
On Friday, several protesters assaulted the officer while he attempted to make an arrest, said Officer Johnna Watson, an Oakland police spokeswoman. The injured officer was taken to a local hospital and later released.
At least two other officers were pepper-sprayed and treated at the scene, said Watson, who added that the march was mainly nonviolent.
"A majority of the crowd was peaceful, but there were some individuals and groups who participated in assaulting police, vandalizing businesses and committing graffiti along the march route," Watson said.
The protest began outside Oakland City Hall, the site of a peaceful gathering the previous day. Marchers encountered several Oakland police officers, some in riot helmets, blocking a freeway on-ramp to keep them from walking onto Interstate 880 - as some did to protest the fatal shooting of Florida teen Trayvon Martin in 2012.
As nightfall approached, a few protesters with covered faces pulled out paint cans and hammers and sprayed anti-police graffiti on buildings as the march continued along a main Oakland thoroughfare into the neighboring city of Berkeley.
Oakland police later arrested two men in their 40s, one for assaulting an officer and the other for obstructing and resisting police, Watson said.
In Berkeley, where protesters set a trash can on fire, at least two people were arrested Friday for resisting or obstructing an officer, said Officer Jennifer Coats, a Berkeley police spokeswoman.