SAN FRANCISCO " Officials have concealed the Olympic torch after the flame's opening ceremony and have not revealed where the planned relay will take place.
At the opening ceremony Wednesday afternoon, the first torchbearer took the flame from a lantern brought to the stage and held it aloft before quickly departing again into a warehouse.
The torch never emerged again from the building, and officials have been tight-lipped about its location.
Shortly before the ceremony began, San Francisco officials cut the original six-mile route nearly in half. The flame's only North American stop has drawn thousands of demonstrators gathered to praise and condemn China during the flame's journey to Beijing.
Thousands of people carrying Tibetan and Chinese flags packed the relay route of the Olympic torch Wednesday and police sought to keep demonstrators from disrupting the flame's symbolic journey to the Beijing Games.
There were signs of tension even before the torch relay began. Pro-Tibet and pro-China groups were given side-by-side permits to demonstrate, and representatives from both sides spilled from their sanctioned sites across a major street and shouted at each other nose to nose, with no visible police presence to separate them.
"A lot of Tibetan people are getting killed," said Kunga Yeshi, 18, who had traveled here from Salt Lake City. "The Chinese said they'd change if they got the Olympics, but they still won't change."
Farther along the six-mile route, about 200 Chinese college students mobbed a car carrying two people waving Tibetan flags in front of the city's Pier 39 tourist destination. The students, who arrived by bus from the University of California, Davis, banged drums and chanted "Go Olympics" in Chinese.
"I'm proud to be Chinese and I'm outraged because there are so many people who are so ignorant they don't know Tibet is part of China," Yi Che said. "It was and is and will forever be part of China."
The torch's 85,000-mile, 20-nation global journey is the longest in Olympic history, and is meant to build excitement for the Beijing Games. But it has also been targeted by activists angered over China's human rights record, prompting officials to warn they might make a last-minute change to the relay route.
The route runs along San Francisco Bay from the city's major league baseball stadium north to Fisherman's Wharf.
Outside AT&T Park, hundreds of pro-China and pro-Tibet blew whistles and waved flags as they faced off near site of the relay's opening ceremony.
Police struggled to keep the groups apart. At least one protester was detained, and officers blocked public access to bridge leading to the ceremony site across McCovey Cove from the ballpark.
About 80 people were expected to carry the torch on its six-mile route, including former San Francisco Mayor Willie Brown.
Ex-football star and former Olympic bobsledder Herschel Walker, 46, was selected to carry it as part of the six-member squad appointed by Samsung, one of three corporate sponsors of the relay.
Former Olympic beach volleyball gold medalist Kerri Walsh, 29, was appointed by sponsor Lenovo, while the swimmer Natalie Coughlin, who holds the world record for the 100-meter backstroke, was chosen to represent the U.S. Olympic Committee.
Zhou Wenzhon, 62, China's ambassador to the U.S. also was scheduled to participate.
One of the runners who planned to carry the torch dropped out earlier this week because of safety concerns, officials said. The torch bearers will compete not only with people protesting China's grip on Tibet, but its support for the governments of Myanmar and Sudan.
Three blocks from the waterfront torch route, a few dozen activists with the Washington-based Save Darfur group, sought to get their message out.
Among them were Ben Cohen and Jerry Greenfield, of Ben & Jerry's ice cream fame, who stood near a van sporting a six-foot-tall stainless steel torch " complete with gas-fired flame " resembling the Olympic torch.
"We're asking China to extinguish the flames of genocide in Darfur," Cohen said. "China is the one country that has enough influence with Sudan to end the genocide. They really have no choice but to use that influence."
Local officials say they support the diversity of viewpoints, but have tightened security following chaotic protests during the torch's stops in London and Paris and a demonstration Monday in which activists hung banners from the Golden Gate bridge.
Ambulances were to be stationed along the torch's route, and extra sheriff's deputies and state law enforcement officers were put on patrol.
Vans were deployed to haul away arrested protesters, and the FAA restricted flights over the city to media helicopters, medical emergency carriers and law enforcement aircraft. Law enforcement agencies erected metal barricades and readied running shoes, bicycles and motorcycles for officers preparing to shadow the runners.
The Olympic flame began its worldwide trek from Ancient Olympia in Greece to Beijing on March 24, and was the focus of protests right from the start.
San Francisco was chosen to host the relay in part because of its large Chinese-American population.
IOC president Jacques Rogge met with Chinese Premier Wen Jiabao on Wednesday to discuss preparations for the games, and "a range of games topics were discussed," the IOC said.
Rogge is to give more details at a news conference Friday, when the IOC's executive board is to discuss Friday whether to end the remaining international legs of the relay after San Francisco because of widespread protest. The torch is scheduled to travel to Buenos Aires, Argentina, and then to a dozen other countries before arriving in China on May 4. The Olympics begin Aug. 8.
Rogge has refrained from criticizing China, saying he prefers to engage in "silent diplomacy" with the Chinese.
In an interview broadcast Wednesday on the VRT television network in his native Belgium, Rogge warned that pushing China too hard on Tibet and human rights would be counterproductive.
"If you know China, you know that mounting the barricades and using tough language will have the opposite effect," he said. "China will close itself off from the rest of the world, which, don't forget it, it has done for some 2,000 years."
"We recognize the right for people to protest and express their views, but it should be nonviolent. We are very sad for all the athletes and the people who expected so much from the run and have been spoiled of their joy," Rogge said.
Meanwhile Wednesday, the White House said anew that Bush would attend the Olympics, but left open the possibility that he would skip the opening ceremonies.
Asked whether Bush would go to that portion of the games, White House press secretary Dana Perino demurred, citing the fluid nature of a foreign trip schedule this far out and the many factors that go into devising it.
"I would again reiterate that the president has been very clear that he believes that the right thing for him to do is to continue to press the Chinese on a range of issues, from human rights and democracy, political speech freedoms and religious tolerance, and to do that publicly and privately, before, during and after the Olympics," she said.