Tokyo sends team to disputed islands

China's state-run media immediately declared the survey  "illegal."

According to CNN, the incident is the latest in rising territorial tensions in North Asia.

The uninhabited islands are known in Japan as Senkaku and in China as Diaoyu, and are privately-owned by a Japanese family.

But both China and Japan separately claim them as part of their territory. The islands, located between Taiwan and Okinawa, sit among rich fishing waters and are also believed to be rich in oil resources.

For now, the Japanese government leases the island from the family to "peacefully and stably maintain" them, as Chief Cabinet Secretary Osamu Fujimura said .

But Tokyo Governor Shintaro Ishihara has begun talks with the private owners and said he expects to strike a deal to buy the islands by the end of the year.

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