A Mongolian-flagged cargo ship Grand Fortune 1 has sunk off the southern coast of South Korea, leaving two dead and 11 missing.

According to the South Korean coast guard officials, the vessel was travelling from the Chongjin region of North Korea’s east coast towards a Chinese port, when the incident occurred.

The 4,300t cargo ship was carrying iron ore and copper power, and had 16 North Korean crew members onboard, of which three were rescued alive from the water.

"Around 12 coastguard vessels, helicopters and civilian cargo ships have been called in to search for the remaining 11 crew members."

The three rescued crew members were taken to a South Korean hospital on the southern resort island of Jeju for treatment.

According to coast guard officials, the ship sent out a distress call from international waters about 80 miles south of the southern port city of Yeosu.

South Korea coast guard spokesman said that around 12 coastguard vessels, helicopters and civilian cargo ships have been called in to search for the remaining 11 crew members.

South Korea coast guard chief Kim Sang-Bae said the search and rescue operation has been hampered by strong winds and high waves, and has requested Japan’s coastguard to assist.

The cause of the incident is not yet known, but officials said they will be speaking to the survivors.