The Olympic flame arrived in San Francisco on Tuesday for its only US stop amid a series of protests and calls for a boycott of the Beijing games over China's human rights record.
Television networks showed the flame arriving around 4:00 am (1630 IST), amid intense security one day after the symbolic Olympic torch was snuffed out five times in Paris to protect it from demonstrators protesting China's crackdown in Tibet.
San Francisco police were gearing up for attempts to disrupt the torch's progress through the city's streets in a relay run on Wednesday.
On Monday, San Francisco activists climbed the famed Golden Gate Bridge to unfurl huge pro-Tibet banners ahead of the symbolic flame's arrival.
Mayor Gavin Newsom on Monday said the route for the relay would be changed and security reinforced to keep protestors at bay.
"We anticipate problems here," he said. "This route is not fixed. It will continue to change and it will change up until the torch is passed -- and even during the middle of the route."
Earlier today a senior Olympic official raised the prospect of abandoning the international legs of the Beijing Games torch relay after protests in London and Paris.
The demonstrators charge China has a poor record of human rights including a crackdown in Tibet and Bejing's reluctance to pressure the Sudanese government over Darfur.
"I am sure it will be discussed," Gunilla Lindberg, a vice president of the International Olympic Committee said when asked if she thought the IOC may scrap the overseas legs of the torch relay.