Occupy Oakland protesters reclaimed the news spotlight after a demonstration last weekend led to 400 arrests and significant damages to City Hall. But as images showed protesters breaking into City Hall, trashing parts of the building, and burning an American flag on its steps, the group now faces growing criticism - even from its own members.

City Hall reopened Monday as Oakland officials decried Occupy's latest string of wreckage: Damage to the City Hall plaza alone has cost the cash-strapped city an estimated $2 million since October, according to Mayor Jean Quan, with another $2 million spent on police overtime and other policing agencies called in to help. At a news conference, a toughened Quan condemned Occupy protesters for their "constant provocation of police with a lot of violence toward them," while urging them to "stop using Oakland as its playground." She also said the city is requesting stay-away orders for about 100 demonstrators who have been arrested numerous times.

Meanwhile Occupy Oakland is fighting back, calling the police arrests of about 400 demonstrators Saturday "completely illegal" and vowing lawsuits. The group's website requested bail fund donations and announced a protest next Monday against police action.

But an unapologetic Interim Police Chief Howard Jordan said officers used tear gas, smoke, and beanbag projectiles to thwart a crowd of about 500 protesters who attempted to break into the Henry J. Kaiser Convention Center. Earlier in the week Occupy organizers said they planned to use the empty building as their new headquarters.

Police reports say protesters ignored officers' orders to disperse and some threw rocks and bottles at them, injuring three officers. "It became clear that the objective of this crowd was not to peacefully assemble and march, but to seek opportunity to further criminal acts," Jordan said at a news conference. He added that while police officers responded to the Occupy protests, the department had difficulty addressing the night's 1,776 calls for service, including 482 calls to 911.

As demonstrators left the convention center and headed to the nearby Oakland Museum of California, protester Yvonne Yen Liu said she witnessed some vandalism, but "I don't think that vandalism is violent," she said. "I don't think it merits the response that we see from the OPD."

Later, police made hundreds of arrests when a group entered a downtown YMCA, while others simultaneously broke in to the City Hall, cutting electrical wires, spraying graffiti, smashing glass display cases, and burning a stolen American flag out front.

Images of a battered City Hall and protesters clashing with police circulated rapidly on the Internet, spurring responses nationwide. Even as the Occupy Wall Street movement declines in numbers and cities continue to eliminate encampments, many protesters across the United States took to the streets to show support for Oakland demonstrators.

White House spokesman Jay Carney said Monday of the protests and an unfolding evacuation of a Washington D.C. Occupy encampment: "We need to balance First Amendment concerns of the right to demonstrate, the right to speak freely, with public safety concerns and public health concerns." Carney said local officials are "weighing those considerations when they make these decisions, and that's appropriate."

In Oakland, city officials expressed growing outrage for the expensive measures required to contain Occupy protests. The group staged two other vandalism-ridden marches last fall that caused temporary shutdowns to the Port of Oakland. Quan's spokeswoman Sue Piper said they're taking a firm, united stance: "All acts of violence, trespassing, property destruction, and overnight lodging will not be tolerated."

Whether Occupy Oakland can hold its front remains in question. After interviewing a number of California college students, UC Berkeley student Christopher Haugh concluded Occupy Oakland is losing its college, youth-centered base. "Regardless of whose fault it is, the West Coast Occupy brand is looking like a street brawl, not a public debate," he wrote in the Daily Beast. "Millennials are turned off by this violence."