Johannes Mehserle received the minimum two-year sentence on his involuntary manslaughter conviction in the killing of Oscar Grant.
Residents in a normally quiet neighborhood wondered why the protesters marched into their part of Oakland.
"I saw like an army full of police guys with their tear guns, gas out and billyclubs like they were just going to beat up someone," said Oakland resident Jestina Broxie. "It was really scary."
Police said they will be looking at video and photographs hoping to identify those who damaged property so charges can be filed.