The row over islands disputed by South Korea and Japan intensifies on Friday as Japan marks "Takeshima Day."

The islands, called Takeshima in Japan and Dokdo in Korea have sullied relations between the two neighbours as they both declare authority over them.

Takeshima Day in Japan was started in 2005 to support Tokyo's claims to territory.

About 40 Japanese activists rallied near the South Korean embassy to mark the day.

South Koreans held a counter protest in front of the Japanese embassy in Seoul.

Children performed a dance to the song "Dokdo is Our Territory."

During the rally, a protester tried to stab himself in opposition to Japan's claims to the island.

Police managed to stop him and he was taken to hospital.

Japan's relations with South Korea frayed badly last year after outgoing South Korean President Lee Myung-bak visited the disputed islands.

South Koreans also harbour bitter resentment of Japanese rule from 1910 to 1945.

The land is now controlled and occupied by Seoul.