Dozens of police in riot gear and hundreds of protesters supporting the Occupy Wall Street movement engaged in a game of cat-and-mouse in downtown Oakland on Tuesday, with authorities using tear gas to respond to demonstrators' repeated agitations.

The latest such skirmish came around 11:15 PDT in front of City Hall, where a haze of chemical smoke still hung in the air following several similar clashes at the site over the course of the night.

It was the fifth time in about three hours that police a fired a volley of tear gas to disperse a crowd at the scene where ongoing tension has erupted into conflict throughout the day.

The number of protesters has diminished with each round of gas. About 200 remained late Tuesday, mostly young adults, some riding bicycles, protecting themselves from the noxious fumes with bandanas and scarves wrapped around their faces.

Police have established a presence in a plaza where a pre-dawn raid Tuesday dismantled an encampment of Occupy Wall Street protesters that had dominated the area for more than two weeks.

Authorities removed about 170 demonstrators who had been staying in the area overnight after repeatedly being warned that such a camp was illegal and they faced arrest by remaining. City officials said 97 people were arrested in the morning raid.

The first evening scuffle broke out after several hundred people made their way back to City Hall in an attempt to re-establish a presence in the area of the disbanded camp.

The protesters had gathered at a downtown library, marched toward City Hall and ultimately were met by police officers in riot gear. Several small skirmishes broke out and officers cleared the area by firing tear gas.

The scene has repeated itself several times since. But each time officers move to disperse the crowd, protesters quickly gather again in assemblies that authorities have declared illegal. Tensions rise as protesters edge closer to police line and climax when someone throws a bottle or rock and authorities response with volleys of gas.

Police have denied reports that they used flash bang canisters to help break up the crowds, saying the loud noises came from large firecrackers thrown at police by protesters.

Helicopters scanned the area late Tuesday and scores of officers wearing helmets and carrying clubs patrolled the streets. Fire crews responded to small blazes in trash containers.

Protesters moved about uneasily even as one used a bull horn to express his resolve.

"This movement is more than just the people versus the police," Mario Fernandez said. "It's about the people trying to have their rights to basic services."

He added, "This crowd isn't going anywhere anytime soon."

Acting Police Chief Howard Jordan told reporters at a late night news conference that authorities had no other choice, saying the protesters were throwing rocks and bottles at officers.

"We had to deploy gas to stop the crowd," he said, according to a KCBS report.

City officials say that two officers were injured. At least five protesters were arrested and several others injured in the evening clashes.

The Oakland site was among numerous camps that have sprung up around the country, as protesters rally against what they see as corporate greed and a wide range of other economic issues. The protests have attracted a wide range of people, including college students looking for work and the homeless.

In Oakland, tensions between the city and protesters have been escalating since last week as officials complained about what they described as deteriorating safety, sanitation and health issues at the site of the dismantled camp.

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Associated Press reporter Marcus Wohlsen contributed to this report.