Three Chinese ships in disputed waters: Japan

This photo, taken by the Japan Coast Guard on April 23, 2013, shows a Chinese marine surveillance ship cruising near the disputed islets -- known as the Senkaku in Japan and Diaoyu islands in China -- in the East China Sea. Three Chinese government ships have sailed into waters around disputed islands controlled by Tokyo, according to the Japanese coastguard. (Japan Coast Guard/AFP/File)

Three Chinese government ships sailed into waters around disputed islands controlled by Tokyo for about five hours on Saturday, the Japanese coastguard said.

The maritime surveillance vessels entered the 12-nautical-mile zone off Uotsurijima, one of the Senkaku islands, which China calls the Diaoyus, in the East China Sea shortly after 9:30 am (0030 GMT).

They were seen leaving the zone at around 2:30 pm, the coastguard said.

Ships from the two countries have been involved in a stand-off as Beijing and Tokyo jostle over ownership of the strategically important and resource-rich islands.

A territorial row that dates back four decades reignited last September when Tokyo nationalised three islands in the chain, in what it said was a mere administrative change of ownership.