Police estimated about 125 protesters gathered in Frank Ogawa Plaza at around 8 p.m. and began marching about an hour later.
Officers followed the march as it wound through downtown streets for several hours.
Two were arrested, one for allegedly moving a Dumpster into the street as a barricade, and the other for interfering with that arrest, police said.
Police issued warnings earlier in the night that marchers may attempt to destroy private property or provoke violence against the police.
An announcement of the march posted to Facebook suggested protesters target police and media property, and set fires in the streets.
The march is the second in what organizers say will be a weekly anti-police march on Saturday night.
Last week, six were arrested in clashes with police for a variety of charges including vandalism, assaulting police officers and possession of explosives.