Possibly one of the most unsettling mysteries in recent maritime history has been discovered in Japanese waters. Over the past two months, about 12 old, heavy wooden boats have been found drifting aimlessly in the Sea of Japan. When investigated, the vessels contained some very disturbing cargo - the decaying bodies of 22 people, according to CNN.

All the bodies are said to be "partially skeletonized," which suggests that the vessels must have been drifting in the sea for some time. Even more disturbing was the fact that one ship contained two headless bodies, while six skulls were found in another.

The first boat was reported to have been sighted in October, followed by a series of discoveries in late November, reports The Examiner.

The Japanese coast guard have provided some theories as to the origin of the ghost ships, the most probable of which being that the boats might have been vessels used in a series of ill-fated attempts to defect from North Korea. This theory is rooted in the words found on one of the boats, which read "Korean People's Army" in Hangul, the Korean Alphabet.

Another clue is a tattered scrap of cloth found on one of the boats, which seem to have been part of the North Korean flag.

Yoshihiko Yamada, a maritime expert, has stated that the vessels bear a striking resemblance to those commonly used by defectors from North Korea. He believes that boats' age and outdated design might have been the reason why the ships never made it to their intended destination, according to MSN News.

"The boats are made of wood and are old and heavy. They can't travel very fast and the engines are not powerful enough to turn the ships against the currents," he said.

John Nilsson-Wright, head of the Asia program at the Chatham House policy institute, is convinced that the boats were carrying people who were attempting to escape the hard life in the reclusive Communist regime.

"What we do know is that for those people living outside of Pyongyang, life remains extraordinarily hard, and it may be an economic necessity as much as a desire for political freedom that is encouraging some people in the North to try and leave the country," he said.

With the lack of other concrete information however, the mystery of Japan's ghost ships remain unsolved.

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