North Korea has reportedly put heavy restrictions on civilian fishing vessels looking to enter the East Sea without monitors.

Washington-based Radio Free Asia (RFA) quoted a Chinese seafood trader as saying that North Korean authorities were strictly controlling fishing vessels that are looking to take advantage of the peak season for cuttlefish in the East Sea, which begins in mid-June. He reportedly said that North Korean fishermen are having difficulties getting permits for entry into the East Sea.

The trader said that even during other times of the year, three or four fishing vessels are grouped together to prevent defectors from fleeing for Japan or South Korea.

There have reportedly been five occasions this year of North Koreans defecting via the sea.