Boat is latest of more than 150 suspected North Korean vessels to be found on Japan’s coast or drifting in its waters.

The badly decomposed bodies of seven people have been found in a suspected North Korean fishing boat that washed up on a Japanese island, a coastguard official said on Sunday.

The remains were found on Saturday on the shore of Sado Island, which lies off the east coast of Japan and is approximately 900 kilometres (560 miles) from North Korea.

“Five of the bodies were identified as men, but the remaining two could not be identified” as they were badly decomposed, the official told AFP.

“There have been similar cases but this was the first discovery of bodies in such a wrecked boat on this island this year,” the official added.

Korean alphabet and numbers were painted on the wooden hull, which was broken in half, he said, adding that there was nothing to show the nationality of those who had been on board.

Local media said Japanese police and coastguard were investigating the case, suspecting the vessel had left from North Korea.

Numbers and letters are on the wooden boat that was found on Sado island in Japan [Sado Coast Guard Station/via Reuters]

So far this year, at least 156 suspected North Korean fishing vessels have been washed up on Japan’s coast or found drifting in Japanese waters, according to the Yomiuri Shimbun.

Experts say some North Korean fishermen are travelling far out to sea in order to satisfy government mandates for bigger catches.

But their old and poorly equipped vessels are prone to mechanical and other problems, including running out of fuel, and there are few ways for them to call for rescue.

Some of the boats wash up on Japanese shores with dead crews, referred to as “ghosts ships” by local media.

Last year, 10 North Koreans rescued from a tiny wooden boat drifting off northern Japan were deported.

In October, about 60 members of a North Korean fishing boat were rescued in the Sea of Japan after it sank following a collision with a Japanese patrol vessel.