The crew of a South Korean cargo vessel presumed to have been hijacked by Somali pirates in the Gulf of Aden is confirmed safe.

The Foreign Ministry in Seoul says that commandoes of South Korea's Cheonghae naval unit boarded the Hanjin Tianjin at around 7:5 on Thursday evening and found all its crew members safe in the ship's citadel.

A ministry official said that the commandoes were searching the ship, but no pirates were found aboard the 75-thousand-ton container vessel.

The freighter lost contact with its operator Hanjin Shipping after emitting a distress signal early Thursday morning about 400 kilometers east of the Yemeni island of Socotra. The Panama-registered ship was sailing to Singapore from Europe with 14 South Korean and six Indonesian crew members on board.

The South Korean Foreign Ministry said earlier in the day that the cargo ship was presumed to have been hijacked by Somali pirates.

A navy helicopter from the South Korean destroyer Choi Young which was deployed in the Gulf of Aden to protect South Korean vessels flew to the Hanjin Tianjin and reported seeing a stream of smoke rising from the ship.