Chinese activists landed on an island claimed by Japan and China on Wednesday and five were arrested as tension between Japan and its Asian neighbors escalated on the 67th anniversary of the end of World War Two.
South Korea prompted an official protest from Japan after comments by South Korean President Lee Myung-bak which some saw as going too far by insulting Japanese Emperor Akihito.
And adding to a day of drama and underscoring how history haunts Tokyo's ties with Beijing and Seoul, two Japanese cabinet ministers paid homage at a controversial Tokyo shrine for the war dead.
Memories of Japan's wartime occupation of much of China and colonization of South Korea run deep in the two countries despite close economic ties in one of the world's wealthiest regions.
Japan arrested five members of a group of activists from China, Hong Kong and Macau who landed on the disputed island chain in the East China Sea, Japan's coastguard said. It also swiftly protested over the landing, Kyodo news agency said.
Friction over the disputed chain of uninhabited isles, known as the Senkaku in Japan and the Diaoyu in China and near potentially rich gas deposits, had already been heating up.
"This is the most successful attempt in a decade" to reach the Diaoyus, the activist group said. Several of the men jumped into the water, swam and then waded ashore. The group said its boat had been rammed by the coastguard and hit with water cannon.
A separate feud over rival claims by Seoul and Tokyo to other rocky islands has also intensified, signaling how the region has failed to resolve differences over its past nearly seven decades after its defeat.
The rows in part reflect skepticism over the sincerity of Japan's apologies for wartime and colonial excesses.
On Tuesday, South Korea's Lee told a group of teachers that Emperor Akihito should apologize sincerely if he wants to visit South Korea, saying a repeat of his 1990 expression of "deepest regrets" would not suffice.
TANGLED HISTORY
Japan's foreign ministry said it had lodged a protest with Seoul over the remarks. Akihito has spent much of the past two decades trying to heal the wounds of a war waged in his father's name.
Lee, whose Friday visit to a disputed island frayed ties between the two U.S. allies, called Japan an "important partner that we should work with to open the future".
But in remarks commemorating Korea's liberation from Japan's 1910-1945 rule, he also said the countries' tangled history was "hampering the common march toward a better tomorrow".
He urged Tokyo to do more to resolve a dispute over compensation for Korean women abducted to serve as sex slaves for wartime Japanese soldiers, known by the euphemism "comfort women" in Japan and long a source of friction.
"It was a breach of women's rights committed during wartime as well as a violation of universal human rights and historic justice. We urge the Japanese Government to take responsible measures in this regard," Lee said.
Japan says the matter was closed under a 1965 treaty establishing diplomatic ties. In 1993, Tokyo issued a statement in the name of its then-chief cabinet secretary and two years later set up a fund to make payments to the women, but South Korea say those moves were not official and so not enough.
Speaking at a ceremony marking the war's end on Wednesday, Japanese Prime Minister Yoshihiko Noda acknowledged the "enormous damage and suffering" caused by Japan to other countries, especially in Asia.
"We deeply reflect upon (that) and express our deepest condolences to the victims and their families," he said, vowing that Japan would never go to war again.
Tapping into anti-Japanese sentiment remains a way to seek public support in South Korea and China, which face leadership changes in coming months. And some experts see a new strain of nationalism is surfacing in Japan amid gloom about the future.
In a sign of the domestic pressures in Japan, National Public Safety Commission Chairman Jin Matsubara and Transport Minister Yuichiro Hata visited the Yasukuni shrine for war dead, defying Noda's urgings to stay away.
Many see the shrine as a symbol of Japan's past militarism because 14 Japanese wartime leaders convicted as war criminals by an Allied tribunal are honored there with Japan's war dead.
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