South Korean university students burned a Japanese flag in Seoul for the second consecutive day on Wednesday in protest of the Tokyo government's claim to South Korea's easternmost islets of Dokdo.

Members of the Korean Progressive University Student Union set the Rising Sun Flag, formerly used by the Japanese imperial army, on fire in front of Dongnimmun (independence) Gate in central Seoul in the afternoon after condemning the Japanese government and Tokyo Olympics organizers for claiming Dokdo.

They left the scene soon after spraying inflammables on the Japanese flag with writing saying "Tokyo Olympics (organizers) and the Japanese government are strongly condemned for claiming Dokdo as Japanese territory" and setting it on fire. The stone gate was built in 1897 during the Korean Empire era to inspire the spirit of independence among the people.

Police said they were investigating whether the students violated the assembly and demonstration law because their act of burning a Japanese flag was committed during an unreported gathering.

On Tuesday, three members of the same activist group were arrested by police for burning a similar Japanese flag near the Japanese Embassy in downtown Seoul.

Seoul's foreign ministry called in a senior Japanese diplomat on the same day to lodge a protest over a map on the Tokyo Olympic website showing Dokdo as part of Japanese territory.

South Korea has maintained a small Coast Guard unit on Dokdo since 1954 in a show of its effective control of the East Sea islets, but Japan has claimed sovereignty over the territory, which is rich in fish and hydrate gas. (Yonhap)