This is just the beginning, there are dozens of other Occupier sites around the country that are going to have to be cleared out when the city can’t take it anymore.

(SF Gate) — Supporters of Occupy Oakland clashed with police this evening while trying to retake an encampment outside City Hall that hundreds of police officers had cleared out 12 hours earlier.

A crowd of about 400 people marched from the public library at 14th and Madison streets toward Frank Ogawa Plaza at about 5 p.m., promising a confrontation with police, who had the plaza barricaded.

The crowd grew as protesters marched around several downtown streets, but police kept demonstrators away from the former Occupy Oakland encampment outside City Hall at 14th and Broadway.

There were some violent exchanges, although by 6:40 p.m. most of the protesters were simply marching.

Earlier, when officers in riot gear went to arrest one protester, about 50 more surrounded them shouting, “Let him go, let him go.”

Protesters threw turquoise and red paint at the riot police officers’ faces and helmets. Some led the crowd in chanting, “This is why we call you pigs.” Protesters trying to fight with police were clubbed and kicked in return.

Police shot flash-bang grenades over the protesters at Eighth and Washington streets to try to get them to disperse.