SAN FRANCISCO -- San Francisco police and public works crews dismantled a Financial District encampment early Thursday that had been occupied for nearly a week by activists protesting economic inequality.

Protesters with the group Occupy SF said about 80 officers wearing riot helmets confronted 200 campers and their supporters at about 12:45 a.m. The officers guarded city workers who removed tents, lean-tos, sleeping bags and other belongings from outside the Federal Reserve Bank building at 101 Market St. near Main Street.

One protester was arrested for allegedly assaulting an officer.

Police said that only one squad of fewer than 20 officers had been on the scene to help public works crews remove nine truckloads of tents, wood pallets and trash.

The camp was taken down hours after several hundred people marched through the Financial District in an Occupy SF-organized protest. The group formed in solidarity with the Occupy Wall Street movement, which has been staging protests in New York over what it calls corporate greed and the excessive concentration of wealth and power among 1 percent of the nation's population.

Weeklong encampment

The Occupy SF camp formed outside the Federal Reserve Bank a week ago Thursday. By Wednesday it had grown to about 50 people.

At around 9:30 p.m. Wednesday, police handed a notice to Occupy SF protesters that although the city and Police Department "celebrate and protect" free speech and the right to assemble, their encampment violated several city laws. They included a ban on having an open flame on a street or sidewalk, creating a public nuisance, disorderly conduct in lodging and serving food without a permit.

Protesters began taking down tents and removing belongings, activists said Thursday, but also posted the police notice online. More than 100 supporters subsequently arrived at the encampment.

At 12:45 a.m., Department of Public Works employees arrived in trucks and began removing campers' possessions as police stood guard.

"They took everything," said one protester, who asked to be identified only as Leslie M. "They said if we showed an effort that we were removing our stuff and taking down our tents, it would be OK."

Tried to stop truck

About 50 protesters stood in front of one truck to try to prevent it from leaving, activists said. The trucks took an alternate route and drove away on Main Street.

Police arrested Kevin Hernandez, 26, for allegedly punching and threatening an officer and resisting arrest, said Officer Albie Esparza, a department spokesman.

Several protesters said the officers had used excessive force in removing the camp.

Esparza said he had received no complaints of excessive force. He said police had broken up the camp not to damage the movement, but because it was posing a public safety risk.

Activists said they tried moving on to Justin Herman Plaza on Thursday, but that police told them they could not. They said they would return to the Federal Reserve Bank to spend the night in sleeping bags.

Police fenced off the entrance of the building and stood guard.

Mayor Ed Lee issued a statement saying he would work with police to safeguard protesters' free speech rights while also keeping sidewalks and streets clear.

Avalos at the camp

Supervisor John Avalos said he was at the camp Wednesday night after police served notice, but left shortly before city crews moved in.

"With our unemployment rate nearing 10 percent, we have a responsibility to be a sanctuary for the 99 percent," Avalos said. "Instead, last night we witnessed that 99 percent being detained, arrested and intimidated with force."