TOKYO • Japan has lodged a protest with Pyongyang after one of its patrol vessels was chased by an apparently armed fishing boat believed to be from North Korea, the government said yesterday.
The incident occurred last Friday in the Sea of Japan (East Sea) and within Japan's exclusive economic zone, which extends 200 nautical miles from the coast, Tokyo said.
The fisheries agency ship was on patrol when it was pursued by "a vessel of unknown origin which had what appeared to be a gun", top government spokesman Yoshihide Suga told reporters.
"The patrol ship suffered no damage as it urgently left the area for safety," he said. "Given the high possibility that the vessel is linked to North Korea, we have lodged a strong protest through the embassies in Beijing." Mr Suga added that Japan had observed the ship's crew and collected other information.
Japan and North Korea do not have diplomatic relations, but Tokyo sometimes makes diplomatic protests to Pyongyang by having its embassy in the Chinese capital contact North Korea's.
Japan's Sankei Shimbun newspaper, quoting fisheries agency sources, said the North Korean ship pointed the gun at the Japanese vessel. News reports said the incident took place near a squid-fishing area where North Korean ships often operate.
Separately, an undersea earthquake off the coast of North Korea early yesterday raised questions over whether it was caused by a nuclear test. The 5.9-magnitude quake struck about 190km south-east of the North's third-largest city, Chongjin, according to the United States Geological Survey (USGS).
North Korea, which has staged five nuclear tests, causes seismic events when it conducts underground nuclear bomb tests.
The USGS said there was nothing to indicate the quake yesterday was a man-made event. Geophysicist John Bellini said the temblor, which did not trigger a tsunami warning, occurred very deep, at 538km below the seabed. The Pentagon confirmed that initial indications showed the quake did not result from a nuclear test.