A Chinese research ship was found operating in Japan's exclusive economic zone near the Japanese-administered, China-claimed Senkaku Islands on Tuesday and asserted its operations were authorized by the Chinese government, the Japan Coast Guard said.
As the Discoverer2 owned by a Chinese oil company was sailing with a wire lowered into the water in the afternoon, a Japanese Coast Guard patrol vessel urged the Chinese ship to suspend the unauthorized research operations in the Japanese EEZ.
"Our operations have been authorized by the Chinese government. This is China's exclusive economic zone," a coast guard official quoted the Chinese ship as saying in response.
The Discoverer2 conducted similar operations there Monday and left the zone once by early Tuesday.
The coast guard also said four Chinese maritime surveillance vessels remained for some eight hours in Japan's territorial waters around the islands in the East China Sea on Monday and left the contiguous zone surrounding the waters by Tuesday morning.
A Chinese fishing surveillance vessel repeatedly entered and left the contiguous zone Monday and Tuesday, the coast guard said.