Though a shadow of its former self, the Occupy movement rages on in Oakland, California, where clashes with police on Saturday night resulted in 400 arrests and significant damage to City Hall. The week prior, Occupy Oakland organizers announced plans to seize an empty downtown building as their headquarters. The protests then began peacefully on Saturday afternoon, The San Francisco Chronicle reports, with over 1,000 supporters gathering at a lunchtime rally in Frank Ogawa Plaza, before marching downtown. But as night fell, skirmishes broke out in the otherwise abandoned streets. Demonstrators threw paint cans and bottles at riot police, who responded by launching tear gas canisters at them  — the same projectiles that gave Iraq War vet Scott Olsen a skull fracture at the Oakland protests last October.

Protesters then managed to force their way into City Hall, and set about vandalizing its lobby, "overturning a model of the city and damaging an exhibit of children's art," the Chronicle reports. An AP report notes that multiple U.S. flags were burned, and that an electrical box had been destroyed. Three officers were injured in the clashes, as well as one protester, who was hit at close range with a bean bag round.

This morning, officials surveyed last night's damage. Oakland Mayor Jean Quan and others inspected smashed display cases and anti-government graffiti sprayed on City Hall walls, and discovered the charred remnants of at least one of the flags.

Occupy Oakland came out fighting today, issuing a news release that claimed the 400 arrests were illegal:

"Contrary to their own policy, the OPD gave no option of leaving or instruction on how to depart. These arrests are completely illegal, and this will probably result in another class action lawsuit against the OPD, who have already cost Oakland $58 million in lawsuits over the past 10 years," the release said.

Mayor Quan responded by telling the protesters to "stop using Oakland as its playground," the AP reports, and expressed exasperation over the protesters' stubborn reliance on violent tactics:

"People in the community and people in the Occupy movement have to stop making excuses for this behavior," Quan said. [...]

"I'm mostly frustrated because it appears that most of them constantly come from outside ofOakland," Quan said. "I think a lot of the young people who come to these demonstrations think they're being revolutionary when they're really hurting the people they claim that they are representing."

It's worth nothing that Quan herself was only recently investigated for disturbing the peace. In 2010, the then-City Councilwoman had allegedly joined a human line that blocked riot police from moving down a major thoroughfare, where demonstrators were protesting a verdict of involuntary manslaughter lodged by a Los Angeles jury against BART police Officer Johannes Mehserle, who fatally shot Oscar Grant, an unarmed passenger. Quan insisted her actions were intended to "to keep things peaceful and help keep the police from overreacting and equally keep the crowd from overreacting," the Chronicle reported her as saying.