The Olympic torch arrived on Sunday in South Korea on the latest leg of its world tour, with demonstrators vowing to disrupt its run through the city that hosted the 1988 Summer Games.
The torch relay was to begin later Sunday from a park built for the Seoul Olympics and make a 24-kilometer (15-mile) journey to City Hall, although organisers have refused to reveal the exact course because of concern over disruptions.
Some 8,000 riot police were being deployed to guard the flame, along with some 100 officers with marathon-running experience to follow the torch in shifts. Officials say they will arrest anyone who tries to interrupt the relay.
Demonstrations are common in South Korea and police have long experience corralling large crowds, from the 1980s pro-democracy movement to recent protests against a free-trade agreement with the United States.
Activist groups say they will try to block the torch as a protest against Chinese policies on North Korean refugees and its crackdown in Tibet.
Han Chang Kwon, head of a coalition of groups representing North Korean defectors in South Korea, decried Beijing's policy of deporting North Koreans caught fleeing their impoverished homeland. "While trying to improve its image with the Olympics, (China) keeps sending defectors to the North knowing they would be executed or sent to political prisons," Han said.
Two South Koreans who had been chosen to run in the torch relay said they would boycott the event to protest China's crackdown in Tibet.
The torch arrived in Seoul from another Olympic host city: Nagano, Japan, site of the 1998 Winter Games. Although there were some minor attempts to halt the run, anti-torch demonstrators were outnumbered by Chinese boosters.
Following Seoul, the torch will be flown to North Korea for its first-ever run in the communist country Monday. The North is an authoritarian state that tolerates no dissent, and no disruptions were expected there.