Occupy Oakland protesters converged on Frank Ogawa Plaza Monday afternoon, where tense confrontations with police occurred over demonstrators' use of a loudspeaker.

The protesters began gathering at the plaza at noon, using an amplified sound system they did not have a permit for, according to police.

Meanwhile, dozens of counter-protesters who oppose the Occupy Oakland movement gathered for a quiet demonstration on the steps of City Hall.

Around 12:30 p.m., police used their own loudspeaker to inform the Occupy Oakland group, which consisted of about 100 people, that they could not use amplified sound.

Police gave them a five-minute warning before officers in riot gear moved in and confiscated the protesters' sound system.

Oakland police spokesman Officer Jeff Thomason said no arrests were made.

Brian Glasscock, 20, who identified himself as a Laney College student studying baking and pastry, said it was his sound system that was seized. He said the equipment is worth between $700 and $1,000, and worried whether he would get it back.

Glasscock said police haven't cracked down on amplified sound during past protests, and wondered why they did so Monday.

"We don't think we need a permit to be in a public space for peaceful assembly," he said.

Police spokeswoman Johnna Watson said police sometimes allow amplified sound without a permit, especially if the activity is not disrupting business or eliciting complaints. But on Monday, she said, businesses near the plaza were complaining about the noise.

Occupy Oakland protester Adam Katz noted that there were more than three-dozen officers at the plaza Monday afternoon. He said police should be focusing on investigating several shootings that occurred over the weekend rather than monitoring protests.

Daud Abdullah, an Oakland resident who was part of the counter-protest, agreed that police resources would be better spent elsewhere but blamed the protesters.

He said he lives in Maxwell Park and that police have been too distracted by Occupy protests to crack down on drug dealing in his neighborhood.

"Oakland residents are fed up with the whole movement and what goes along with it," Abdullah said.

He said the leaders of Occupy Oakland should get rid of the violent fringe elements of their group.

Paul Junge, public policy director for the Oakland Metropolitan Chamber of Commerce, was also part of the counter-protest, which he said was organized by the group Stand for Oakland.

"Causing vandalism, distracting police ... we've had enough of that," Junge said. "It shouldn't be destructive to the city."

Monday afternoon's protest follows a smaller gathering that morning at the Wiley Manuel Courthouse, where 10 Occupy Oakland protesters were arraigned on charges stemming from a Jan. 4 demonstration.

About two-dozen protesters gathered at the courthouse for the hearing, drinking coffee and eating bagels and bacon next to a sign outside the courthouse that read "Bacon Not Pigs."

After the hearing protesters' attorney, Frank Viola of the National Lawyers Guild, said the fact that the protesters were only being charged with obstructing a sidewalk indicates to him that there's not much of a case against them and that the arrests were "a thin attempt to violate their civil rights."

Viola said the demonstrators were only "raising their voices for the 99 percent" and speaking out against inequality.

"This is a political struggle, and we'll fight in the streets and fight in the courts if necessary," Viola said.

Shortly after 1 p.m. Occupy Oakland protesters began marching back to the courthouse.