Two men were arrested and a police officer was taken to a hospital during an anti-police march through downtown Oakland, police said.
The planned march Friday was one of a number of protests happening nationwide, reported KTVU-TV in Oakland, after unarmed teenager Michael Brown was fatally shot by police in Ferguson, Missouri, last weekend.
Police said a small group of Oakland protesters pepper sprayed officers, the station reported, adding that one police officer was assaulted by several people while trying to make an arrest and had to be taken to a hospital.
A 45-year-old Oakland man was arrested in connection the assault, KTVU reported, citing police. About two hours later a 41-year-old Hayward, California, man was arrested on suspicion of obstructing, delaying and resisting police officers, the station added, citing police.
The protestors also vandalized businesses, broke windows, disrupted traffic, and tagged the area with graffiti, KTVU said, citing police.