Many in the crowd outside Oakland City Hall shouted "Burn it! Burn it!" as masked protesters readied to set fire to an American flag. That's when a woman emerged from the scrum, screaming for them to stop, that it would hurt the cause.

OAKLAND, Calif. — Many in the crowd outside Oakland City Hall shouted "Burn it! Burn it!" as masked protesters readied to set fire to an American flag. That's when a woman emerged from the scrum, screaming for them to stop, that it would hurt the cause.

Moments later, the flames began, and suddenly a movement that seemingly vanished weeks ago was back in the spotlight, this time for an act of protest that has long divided the nation and now the movement itself.

The images of the flag-burning went viral in the hours after Saturday's demonstrations on Oakland's streets, with Occupy supporters denouncing the act as unpatriotic and a black mark on the movement. Others called it justified.

The flag-burning, however, raised questions about whether the act will tarnish a movement of largely peaceful protests and alienate people who agree with its message against corporate excess and economic inequality.

"I'm quite confident that the general view is that violence of this sort — whether it's symbolic or otherwise — is contrary to the spirit of the movement and should be renounced," Columbia University sociologist Todd Gitlin said.

Flag-burning has been a powerful symbol since the days of the anti-Vietnam War movement. Congress at the time passed a law to protect the flag in 1968, and most states followed suit.

In 1989, the U.S. Supreme Court decided such laws were unconstitutional restrictions on free speech. The court's decision set off a move in Congress to pass a constitutional amendment to prohibit desecration of the flag. An attempt in 2006 failed by only one vote in the Senate.

In Oakland, social activism and civic unrest have long marked the rough-edged city across the bay from San Francisco. Beset by poverty, crime and a decades-long tense relationship between the police and residents, its streets have seen many clashes, including anti-draft protests in the 1960s that spilled into town from neighboring Berkeley.

At Occupy Oakland, flag-burning is nothing new. A well-known Bay Area activist burned three during protests that temporarily shut down the Port of Oakland in November.

Troy Johnson, an Occupy Oakland member, said he arrived just in time Saturday to watch his friend, whom he would not name to protect his identity, emerge from City Hall with an American flag in tow.

"He asked the crowd, 'What do you want us to do with the flag?' " Johnson recalled. "They said, 'Burn it! Burn it! Burn it!' "

The fire-starter is not an anarchist, but a typical member of Occupy Oakland who feels the system has failed them, said Johnson, who was a sergeant in the U.S. Army.

"To the veterans who fought for this country, I wholeheartedly apologize," he said. "Because when they took the oath to join the military, they fought for the flag. But they also fought for the right to express ourselves."

Another Occupy member, Sean Palmer, who served in the Marines, said he opposed flag-burning. "I think they should've hung it upside down, because that's the international call for distress and that's what we are, in distress," Palmer said.