China ignored warnings Sunday from Japan's coastguard and conducted surveys near disputed islands in the East China Sea, a news report said. The Japanese coastguard made repeated warnings to the ship against surveys around the rocky Senkaku islands, Japan's news agency Kyodo quoted the coastguard as saying.
The islands, which lie between Taiwan and the southern end of Japan's Okinawan chain, are administered by Japan but also claimed by China, where they are known as Diaoyu.
The coastguard said one of its patrol boats first spotted the 3,235-ton Dongfangfong No 2 survey ship Sunday morning several miles south-west of Uotsuri, the main island in the Senkakus.
The patrol boat tracked, monitored and warned in Chinese and English the Chinese ship which continued its surveys until later that evening, Kyodo said. The coastguard said such surveys and research were not allowed around the islets unless an advance notice was filed.
The Japanese Foreign Ministry lodged a protest with the Chinese Embassy in Tokyo saying there had been no advance notice of Sunday's survey, an official said.
The embassy said it would look into the incident, Kyodo said.
It was China's first survey of the isles in more than a year, the coast guard said, and was likely to inflame relations between the Asian powers which are already divided over wartime history.
Japan-China ties have been badly strained by Japanese Prime Minister Junichiro Koizumi's repeated visits to the Yasukuni shrine, which honours 2.5 million war dead including 14 top war criminals. The Senkaku dispute came to the fore in the early 1970s when China and Taiwan made their claims to the islands after oil deposits were confirmed in the area.
Japan has drawn protests from China and Taiwan for allowing an ultra-nationalist Japanese group to erect a lighthouse and a member of parliament to land on one of the islands. A Hong Kong activist drowned in September 1997 after he jumped overboard when his protest ship, blocked by a Japanese coast guard flotilla, failed to get to the island.