North Korea's leader, Kim Jong Un, has put a high priority on fishing as a way of earning foreign currency and providing a sustainable food source that is not reliant on harvests and weather, Reuters reported.
The Japanese coast guard and police reported 12 incidents of wrecked wooden boats, including some that were in pieces, on the country's shores and waters since October, containing 22 dead bodies, including five skulls, Reuters reported.
A handwritten sign identified one boat as belonging to unit 325 of the North Korean army, according to footage from Japan's NHK Television. Tattered cloth was found aboard the vessel that appeared to come from the North Korean flag, the video showed.
The waters in the Sea of Japan are rougher at this time of year due to cold, northwesterly winds.
"Kim Jong Un has been promoting the fisheries, which could explain why there are more fishing boats going out," Kim Do-hoon, a professor of fisheries science at Bukyong National University in Busan, told Reuters.
"But North Korean boats perform really poorly, with bad engines, risking lives to go far to catch more. Sometimes they drift and fishermen starve to death," he said.