Nearly a dozen wooden boats carrying decomposing bodies have been found in the waters off the coast of Japan over the past two months.
Inside the 11 vessels were at least 25 bodies, according to Japanese broadcaster NHK. Two bodies were headless, and one boat contained six skulls, Singapore's Straits Times newspaper reported, citing the Japanese Coast Guard. The poor condition of the remains suggested that the boats had been adrift for some time, the paper said.
One of the boats had a tattered banner that looked like it could have been part of a North Korean flag. The boat also had a board with Hangul words that said "Korean People's Army," which is the name of the armed forces in North Korea.
A maritime expert said the ships looked like those used by defectors from North Korea.
"They are made of wood and are old and heavy," Yoshihiko Yamada told NHK. "They can't travel very fast and the engines are not powerful enough to turn the ships against the currents."
At least some of the ships also contained fishing equipment. One ship examined by NHK had fish hooks, netting and lights for attracting squid, leading some to think that the ghost ships may have been fishing vessels that ran into trouble.
But most experts seem to believe the people on the ships were trying to defect.
"I would say that defectors would be the most likely explanation, and the fact that there have been so many cases in such a short space of time is worrying because it suggests there is serious instability just below the surface in North Korea," Jun Okumura, a visiting scholar at the Meiji Institute for Global Affairs, told the Telegraph.
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