Thailand Navy says at least six sailors found dead after warship capsize

Race against time as rescuers search for 23 missing marines

The Royal Thai Navy has confirmed the death of at least six marines after a warship capsized off the coast of southern Thailand due to rough weather.

The HTMS Sukhothai – a US-made corvette with 105 members on board – sank 37km off the shore of the Prachuap Khiri Khan province on Sunday night. Seventy-five people were rescued on Monday, the navy said in a tweet.

Thailand's military mobilised two Seahawk helicopters, the HTMS Kraburi warship and unmanned drones off its central coast to scour through the choppy waters in a race against time to find survivors.

Four bodies were recovered nearly 60km from the sunken vessel, navy commander admiral Choengchai Chomchoengpaet said in a briefing on Tuesday. The military later announced that another dead body was found and one of two rescued had succumbed.

Twenty-three people still remained unaccounted for, some without life vests.

Five dead bodies were brought by a helicopter to the Sawangrat Sattha Thammasathan Foundation in Prachuap Province for identification, while the other one remained at the HTMS Bhumibol Adulyadej ship, the navy said in an update on Tuesday evening.

“I’d like to apologise to the families of the deceased,” the admiral said.

The HTMS Sukhothai corvette warship lists off the coast of Prachuap Khiri Khan province (Royal Thai Navy)

Admiral Chonlathis Navanugraha, the navy's chief of staff, said the latest person was found 41 hours from when the ship sank and he was alive.

"So we believe that there are those still alive out there ... we will continue to search."

One of the marines was found late on Monday clinging to a buoy, captain Kraipich Korawee-Paparwit, commander of the HTMS Kraburi, said.

“He was floating in the water for 10 hours. He was still conscious, so we could take him out of the water safely.”

Vice admiral Pichai Lorchusakul, the regional navy commander, said finding the missing men would be critical given their time exposed to the elements. He earlier said the main priority was searching for and rescuing "as many as we can".

The Sukhothai warship, which was on a patrol, suffered an engine malfunction and started taking on water just before midnight on Sunday. Strong winds and over four-metre waves blew seawater onto the corvette knocking its electrical system and the loss of power allowed more water to flow into the vessel, causing it to list and sink.

The first responders suffered a setback on Monday as the strong winds continued to pose a challenge to rescue efforts.

HTMS Kraburi commander Kraiwit Kornraweeprapapitch said slightly improved weather would help the search.

“The format of searching is still the same, which is a joint operation with helicopters,” he said, adding that the vessels are scanning an area roughly 50km by 50km.

People rescued after a Royal Thai Navy ship sank on Sunday (Anadolu Agency via Getty Images)

Captain of the sunken ship lieutenant colonel Pichitchai Tuannadee said he was in the sea for two hours before he scrambled on to a raft and was found by search teams on Monday.

“To see something as small as a life ring or a person’s head above the surface of the water, it’s very hard to see with the big waves,” he said.

He added that the missing sailors were likely to be fatigued by now from having to tread water and make sure those without vests stayed afloat.

The ship’s drowning is a significant blow to the Thai navy which had only seven corvettes. The force has only two Ratanakosin-class corvettes built in the US by Tacoma Boatbuilding Company in the 1980s.