From the BBC:
Demonstrators carrying Tibetan flags marched to the Chinese Consulate to denounce Beijing’s policy on Tibet.
Officials have promised tight security for Wednesday’s torch relay, following chaotic scenes in London and Paris.
Officials in Beijing have condemned the disruption to the torch relay but promised that it will go ahead.
Extra police will line the torch’s route as it travels through San Francisco.
Mayor Gavin Newsom said he had been in touch with officials in the UK and France to discuss ways of handling the protesters.
“I’m not naive to the challenge associated with this event,” he said.
The torch arrived in San Francisco early on Tuesday and was immediately taken to a secret location.
The flame relay will begin at 1300 (2000GMT) and follow a six-mile (10km) route though the city.
Several protests are planned and police say they reserve the right to change the route if necessary.
On Tuesday, activists gathered near City Hall for their march to the Chinese mission and a late-night vigil.
South African Archbishop and Nobel Peace Prize laureate Desmond Tutu urged world leaders not to go to the Games.
“For God’s sake, for the sake of our children, for the sake of their children, for the sake of the beautiful people of Tibet – don’t go,” he said at the vigil.
“Tell your counterparts in Beijing you wanted to come but looked at your schedule and realised you have something else to do.”
Other speakers called for further disruption of the relay.
“This is not about us battling the torchbearers,” Lhadom Tethong, executive director of Students for a Free Tibet, told the crowd.
“This is about the Chinese government using the torch for political purposes. And we’re going to use it right back.”
But in Chinatown, community representatives held a news conference to call for a peaceful relay and voice pride over China’s hosting of the Games.
“If I support the Olympics, of course I don’t support the protests,” local resident Ling Li told the Associated Press News agency.
“This is the first time China has had the Olympics. We should be proud of this.”
International Olympic Committee (IOC) members are to discuss the issue in meetings in Beijing in the coming days, but President Jacques Rogge scotched rumours that the relay might be stopped.
“There is no discussion of cancelling any legs,” he told the Wall Street Journal. “What we will do is study the torch relay so far.”
He is due to meet Chinese Premier Wen Jiabao later in the day.