Tae kwan do 311.
(photo credit: REUTERS)
Conservative South Koreans set a Japanese flag alight at a Seoul rally.
They are marking the 66th anniversary of Korea's liberation from Japanese colonial rule.
There are ongoing tensions about ownership of the Dokdo Islands in the East Sea, a group of islets which both countries claim.
The demonstrators are also against unification with North Korea, with taekwondo masters smashing wooden boards bearing the words, "pro-North Korean groups".
Protest leader Park Hee-Do said, "The Japanese try to invade our Dokdo
Island and North Korea tries to invade our sea border. We will
definitely take revenge on any aggression on our territory and our
Elsewhere, thousands of workers and student activists held a separate rally.
They were protesting against the administration's hardline stance
towards North Korea, and denounced the "influence" of the US over the
The President of the Korean Trade Unions Federation, Lee Young-Deuk says
the government will not stop the unification movement, "Even if Lee
Myung-bak's administration tries to stop our unification movement in
nasty ways, we workers will march toward the peaceful and independent
unification in our own way until the end."
Protesters occupied the streets for two hours, but dispersed when riot police threatened to use water cannons.
The two Koreas station about one million troops in their respective
sides of the Demilitarized zone, while around 40,000 US troops are
posted in the South.