About three-dozen protesters surrounding the tent, pitched on a bocce ball court, were in a standoff with police officers wearing helmets and holding batons, the Bay City News service reported.
The crowd gathered at the Port of San Francisco plaza Wednesday evening for a general assembly meeting after a day of protests in response to a morning police raid of the Occupy SF encampment that led to more than 70 arrests.
Most were arrested for illegal lodging and for being in the park after hours, police said.
Police arrested at least two protesters during demonstrations Wednesday afternoon.
In Washington, 62 protesters disapproving of what they called the excessive influence of corporate money in politics were arrested Wednesday after shutting down the K Street lobbying corridor, in the second mass arrest in the city in four days.
About a dozen more were arrested later at the U.S. Supreme Court.
The protests, which attracted people from across the country, appeared to mark a shift toward a more combative stance by protesters, The Washington Times said.
Thirty-one protesters were arrested Sunday during a daylong standoff with U.S. Park Police that started when protesters refused to dismantle a wood-frame structure they built overnight at the Occupy DC encampment on McPherson Square hear the White House.
The Occupy movement entered the third day of a new phase Thursday in more than 20 states as protesters sought to take over foreclosed houses and turn them over to needy people.
In New York, Occupy Wall Street protesters began fixing up a foreclosed house Wednesday whose ceiling was covered in mold, carpets were mildewed and walls were partially knocked down, The New York Times reported.
The protesters said they intended to transform the house into a home for Tasha Glasgow, 30, her companion and their two young children. The family has been squatting in an apartment, with no water or heat, Glasgow said.
The house, owned by Bank of America, has not issued an eviction notice to force the demonstrators out, the Times said.
Occupy protesters in Oakland, Calif., helped single mother Gayla Newsome and her three daughters move back into the home she lost to foreclosure, the San Francisco Chronicle reported.
"I've moved back in," she told the newspaper, declining to say how she regained access to the three-bedroom townhouse.
"I hope to bring visibility to this issue and get the bank to have a conversation with me," she said.