China’s coastguard said it ordered a Japanese fishing vessel to leave the country’s territorial waters after it “illegally” entered an area surrounding a disputed group of islands in the East China Sea.

A spokesperson for Beijing’s coastguard said on Thursday it “took necessary control measures in accordance with the law, warned [the ship] and expelled it” during the incursion into waters around the Diaoyu Islands – which Tokyo calls the Senkaku Islands – on October 15-16.

“We urge the Japanese side to immediately stop all illegal activities in these waters,” spokesperson Liu Dejun said in a statement.

Japan has yet to comment on this latest incident near the disputed islands.

Tokyo rejects China’s claim over the tiny, uninhabited islands in the East China Sea but beneath which there are believed to be potential undersea oil and gas reserves.

Japan and China have been involved in several confrontations in the disputed waters in recent months.