TOKYO — Regional tensions flared on the emotional anniversary of Japan's World War II surrender, as activists from China and South Korea used Wednesday's occasion to press rival sea territory claims, prompting 14 arrests by Japanese police.
The group had traveled by boat from Hong Kong to a set of uninhabited islands controlled by Japan but also claimed by China and Taiwan. Japanese police initially arrested five activists who swam ashore in the East China Sea chain, known as Senkaku in Japanese and Diaoyu in Chinese.
Japan Coast Guard officers later arrested nine others who stayed on the fishing boat, the Kai Fung 2, including two who had earlier landed on one of the islands called Uotsuri and went back aboard, officials said.
"We want the world to know that this is — way back in history — the territory of China, and as Chinese people we can go there fishing, touring at our own right," David Ko, a spokesman for the activists, said in a telephone interview from Hong Kong. "The Japanese have no right to stop us."
Chinese activists last landed on the island in 1996, and seven of those arrested were repatriated quickly.
China urged Japan to refrain from taking any action that could endanger Chinese citizens or their property, Foreign Ministry spokesman Qin Gang said in a news release.
Japan says it has controlled the five main islands for more than 100 years. Four of them have since been sold to private owners, with the fifth remaining state property.
The government pays rent on the four privately owned islands to keep them from being sold to any questionable buyer.
Chief Cabinet Secretary Osamu Fujimura said Japan historically and by international law owns the islands and there is no room for sovereignty to be questioned. He called the trespassing and arrest "extremely regrettable."
Also Wednesday, a group of South Koreans reached another set of disputed islands controlled by South Korea in a demonstration aimed at belittling Japan's claims to that territory.
The anniversary of Japan's surrender in 1945 revives long-running territorial disputes in Asia as well as emotional memories of Japan's brutal colonial occupation of many neighbors that ended only at the close of the war.
While Japan routinely apologizes for its wartime actions, its politicians often anger neighboring countries by visiting the Yasukuni Shrine, a memorial to Japan's war dead, including top war criminals.
Dozens of Japanese lawmakers visited the shrine Wednesday, including two Cabinet ministers.
At a solemn ceremony elsewhere in Tokyo, Prime Minister Yoshihiko Noda apologized to victims of Japanese atrocities, mourned the dead and renewed Japan's pledge to renounce war.
"We have caused tremendous damage and pain to many countries, particularly the Asian people, during the war. We deeply regret that and sincerely mourn for those who were sacrificed and their relatives," Mr. Noda said. "We will not repeat the same mistake."
Emperor Akihito, whose father made the unprecedented 1945 national radio address announcing that the war could not be won, also offered prayers for the dead.
Simmering tensions between Japan and its neighbors have threatened to boil over in recent weeks.
Last week, South Korean President Lee Myung-bak visited contested islands in the Sea of Japan, called Takeshima in Japanese and Dokdo in Korean. His visit was seen by many as an attempt to play up anti-Japan sentiment ahead of elections later this year.