Tokyo asked Pyongyang Wednesday to capture and hand over two unidentified ships that fled Japanese destroyers in the Sea of Japan earlier in the day if it is confirmed that they entered North Korean territorial waters, according to government officials.

Foreign Minister Masahiko Komura stressed that as of Wednesday afternoon there was no information to conclude the vessels are North Korean. Japan made its request for cooperation through indirect diplomatic channels, such as the North Korean Embassy in Beijing and Pyongyang's U.N. representative in New York, Komura said. Tokyo has no diplomatic relations with Pyongyang.

Russia has conveyed its readiness to share information and take further measures to help catch the two vessels, and Japan has accepted Moscow's offer to cooperate, Komura said. Japan has briefed the United States, South Korea and Russia on the chase. China was also given an explanation Wednesday.

Komura said the ships are suspected of having committed an unlawful act within Japanese territorial waters. He did not elaborate.

60 in Yugoslavia urged to evacuate

Sixty Japanese citizens were in Yugoslavia as of Tuesday when the government issued an evacuation advisory, the Foreign Ministry said Wednesday.

The ministry issued the advisory Tuesday because of the heightened possibility of military intervention by the North Atlantic Treaty Organization over the Yugoslav government's refusal to sign a peace accord with ethnic Albanians in the troubled province of Kosovo.

Of the 60 Japanese that the Japanese Embassy confirmed to be in Yugoslavia, 59 remain in Serbia -- including 51 in Belgrade -- and one in Montenegro, the ministry said. There are no Japanese in Kosovo.