All of the crew were brought to safety without deaths or injuries, Japanese officials said on Thursday. Their ship sank before dawn some 27 kilometers (16.8 miles) of Japan's Fukue island in the East China Sea.

"We are investigating the cause of the accident by interviewing them on our patrol ship offshore," the coast guard spokesman said.

According to the crew, the 6,558-ton vessel was transporting rice from a western port in North Korea to the east of the same country, by taking its load around the entire South Korean part of the peninsula.

The coast guard spokesman said that no decision had been made on what to do with the crew, as Tokyo and Pyongyang have no diplomatic relations. With the recent nuclear test in North Korea adding to the tensions, the animosity between two nations has been steadily stoked by the communist state since Japanese atrocities in World War II.

Rice, which is the staple food in Asia, is also the main product of North Korea's farmers. Many countries boosted their sanctions against Pyongyang recently in response to nuclear and missile tests, leading to worsening lack of food in the desperatelly poor country.

dj/msh (dpa, AFP)