Hong Kong and Vietnamese rescue workers are scrambling to find survivors after a South Korean cargo ship sank in the South China Sea as a result of apparent high waves, with three South Korean and four Myanmar crew still unaccounted for, Seoul officials said Tuesday.

The 15,000-ton bulk carrier was carrying 21 crew when it went down on Monday afternoon while sailing from Malaysia to mainland China. Fourteen crew members, including six South Koreans, were rescued by other commercial ships and rescue workers at the scene, foreign ministry officials said.

Early on Tuesday, Seoul’s foreign ministry had originally reported that four South Korean and eight Myanmar crew were rescued, but two more Koreans were confirmed to have been successfully picked up by a nearby ship later in the day, ministry spokesman Cho Byung-jae said.

“As two more survivors were found on Tuesday morning, we have not given up hope yet and are trying to make utmost efforts to find other survivors,” Cho said.

The South Korean government is closely cooperating with Hong Kong and Vietnamese maritime police to search for the missing crew, Cho said.

Hong Kong police are mobilizing their helicopters to search for survivors near the scene and China was set to deploy two military ships to support the rescue work, ministry officials said.

It was not immediately clear why the ship, named “Bright Ruby,” sank, but officials said it was presumed to be battered by “waves up to five to six meters high and adverse weather conditions.”

Those rescued were being treated on other ships near the scene and no injuries were reported, officials said.

Cho said the ship went down some 350 nautical miles south of Hong Kong waters as of around 4:05 p.m. on Monday (Korean time).

The ship was hijacked by Somali pirates off the Gulf of Aden in September 2008, ministry officials said. The ship and its eight South Korean crewmen were released after 37 days in captivity. 

(Yonhap News)