The troubles in South Korea followed a string of anti-China protests on various legs of the global torch relay – intended by games organisers as a symbol of unity ahead of the opening of the Beijing games in August.
The flame arrived in Vietnam on Tuesday after a trouble-free leg in North Korea.
Sunday's clashes in Seoul erupted when about 300 protesters, including North Koreans, demonstrated against China's forced repatriation of North Korean refugees and its recent crackdown on unrest in Tibet.
March 24 - Human rights protesters breach security to try to disrupt the torch-lighting ceremony in Olympia, Greece
March 30 - Tibet activists try to stop flame entering Athens stadium for handover to Chinese officials
April 6 - Thousands of pro-Tibet protesters line relay route through London, scuffles break out with police and 35 are arrested
April 7 – Flame extinguished at least twice during Paris relay, forcing the torch-carrier onto a bus to escape protesters
April 9 - San Francisco abruptly changes torch route fearing clashes between pro-Tibet protesters and pro-China counter-protesters
April 17 – New Delhi deploys 15,000 police and security guards during radically shortened relay through Indian capital. Dozens of Tibetan exiles arrested
April 19 - 2,000 police protect Bangkok relay as crowd of about 200 China supporters taunt scores of pro-Tibet demonstrators
April 23 - Australian leg of the Olympic torch relay ends without interruption, although several protesters were arrested amid a tight security operation in the capital, Canberra
April 26 – Four people injured in Japanese city of Nagano when protesters opposed to Beijing's rule in Tibet clashed with Chinese supporters
April 27 – Scuffles break out at torch relay between in Seoul, South Korea, between Chinese students and Korean protesters demonstrating against China's human rights record
April 28 – Thousands of supporters watch the Olympic in an incident-free torch relay in the North Korean capital of Pyongyang
More than 6,000 Chinese demonstrators, mostly college students, had also gathered for the start of the relay in Olympic Park.
In one clash between the groups, Chinese students were seen throwing water bottles, stones, chunks of wood and drink cans at the Koreans.
In another incident, Chinese students surrounded and beat up a small group of protesters, witnesses said.
"It is very regrettable that foreigners staged illegal violent protests at a time when self-restraint against violent protests is taking root under a new government," Kim Kyung-Han, South Korea's justice minister, told the country's cabinet.
South Korea's newspaper editorials and internet users also slammed the youths.
"It marked the first time that Chinese have run amok in the capital of a foreign country", the popular Chosun Ilbo newspaper said.
"We cannot but doubt whether China has the common sense and standards to host the Olympic Games," the newspaper said, criticising the government and police for failing to stop the violence.
No major disruptions are expected in Vietnam during the final international leg of the troubled torch relay through Ho Chi Minh City.
However, some Vietnamese students have threatened to hold demonstrations during the relay against China's claim to the disputed Spratly Islands.
In the past, China and Vietnam have clashed militarily over the string of rocky outcrops in the South China Sea thought to contain large oil and gas deposits.
Vietnamese authorities have given few details about the relay, including its route through the city, apparently for security reasons
After Vietnam, the torch will head to the Chinese territories of Hong Kong and Macau before touring the mainland including Tibet.
|Mountaineers are set to attempt an ascent of |
Everest with an altervative torch [Reuters]
Chinese authorities meanwhile have remained tight-lipped about the progress of a separate Olympic flame being carried up Mount Everest.
Shao Shiwei, a media official with the Beijing organising committee for the Olympic games, said the flame is being carried by mountaineers, but did not confirm whether they had begun ascending the mountain, known in China as Mount Qomolangma.
"There are many back-up flames and they did not tell us which one is going to go to the peak," Shao told Reuters news service.
"We are working with prudence because the whole world is watching."
A Nepalese official says an American mountaineer caught on Everest with a "Free Tibet" banner has been deported and that Nepal has banned him from all climbing activities in the nation for two years.