TOKYO: Two Chinese coast guard ships approached a Japanese fishing boat in Japanese territorial waters off the Senkaku Islands on Tuesday, Chief Cabinet Secretary Katsunobu Kato said.

One of the Chinese ships had something like a cannon, Kato told a press conference.

The Chinese ships intruded into Japanese territorial waters off the islands in the East China Sea around 4:15 a.m. (7:15 p.m. Monday GMT) before nearing the fishing boat, Kato said. They left the waters past 10 a.m., he said.

Tensions have heightened around the Japanese-administered Senkaku chain since China earlier this month enforced a new law allowing its coast guard to fire on foreign vessels.

The two vessels joined two other Chinese coast guard ships that sailed near a Japanese fishing boat in Japanese territorial waters off the islands on Monday.

The first two ships were still staying in the waters as of Tuesday morning, in defiance of repeated calls from the Japan Coast Guard to leave.

The Japanese government has been protesting against Beijing for violating international law. China claims the Senkaku Islands and calls them Diaoyu.

JIJI Press