In the past several years, a few dozen empty boats thought to be of North Korean origin have washed ashore annually in prefectures facing the Sea of Japan, especially Niigata and Ishikawa, according to the coast guard.
Although this year's total is likely to be similar, with at least 11 vessels found in a roughly one-month period since late November, the difference this time is that they were carrying people: four survivors and 10 bodies.
While North Koreans have sailed to Japan before in search of asylum, the prevailing view among experts is that the boats arriving on Japan's coasts this year were not manned by people fleeing the isolated country.