A small wooden ship containing eight bodies which had been partly reduced to skeletons has washed up on a beach in the Sea of Japan.
The "ghost ship" was found by the Japan Coast Guard (JCG) in the northern Akita Prefecture, days after two similarly partially decomposed bodies were found on the island of Sado.
Both local police and the JCG believe the two men may have been from North Korea, as what appeared to be North Korean cigarettes and life jackets with Korean lettering were found nearby.
Authorities are working to establish where the bodies found over the last week came from.
Last week, police found eight fishermen who said they were from North Korea on the same western shore.
Seo Yu-suk, research manager of North Korean Studies Institution in Seoul, said North Korea's food shortages could be behind what is potentially a series of accidents involving North Korean ships.
"North Korea pushes so hard for its people to gather more fish so that they can make up their food shortages," he said.
Yoshihiko Yamada, professor at Japan's Tokai University, said fishermen operating in the Sea of Japan have just entered a season of hostile weather conditions.
"During the summer, the Sea of Japan is quite calm. But it starts to get choppy when November comes. It gets dangerous when northwesterly winds start to blow," he said.
A total of 43 wooden ships believed to have come from the Korean peninsula washed up on Japanese shores or were seen to be drifting off Japan's coast from January to 22 November this year, compared with 66 ships for the whole of last year, the JCG said.
Additional reporting by Reuters
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies