Japan has discovered another abandoned boat off its coast, this one with four bodies in it. File photo by jefwod/Shutterstock

TOKYO, Dec. 7 (UPI) -- Japan has discovered an abandoned boat filled with bodies off its coast in another incident of a "ghost ship" perplexing authorities.

Four bodies were found in a 41-foot-long wooden boat on Sunday south of the Ushitaki fishing port in the Sai Village of the Aomori prefecture, CNN reported. Though the boat has no clear identification, it looks similar to other abandoned boats found in the same region in recent months.


The boats featured Korean lettering and markings on their hulls, suggesting they may have arrived from North Korea, an Aomori Coast Guard spokesman told CNN. He said the latest boat is in a deteriorated condition, indicating it may have been adrift for some time.

In the past two and a half months, the Japanese coast guard has discovered at least 12 wooden boats, most in poor shape, either drifting off the coast or beached on land facing North Korea across the Sea of Japan, also known as the East Sea. Some of the boats had fishing gear in them.

At least 25 bodies have been found aboard the vessels. One boat in late November was found with three mostly decomposed bodies. In another boat, two bodies were found without heads. One boat was found with six skulls, The Japan Times reported.

Officials said it is unlikely the boats were being used by North Korean agents to infiltrate Japan or smuggle drugs because they were in such shoddy condition and lacked modern equipment such as radar. Some speculate the boats may have been fishing vessels that drifted too far and and ran out of fuel. Others believe migrants from North Korea seeking better living conditions are the source of the "ghost ships."

One boat was found with "Korean People's Army" written on it and another was found with a tattered scrap of cloth that looks like it came from North Korea's national flag.

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