A warship carrying more than 100 crew members has sank in the Gulf of Thailand during a storm, according to the Thai navy, leaving 31 servicemen unaccounted for.
The HTMAS Sukhothai sank after water flooded its power controls on Sunday night.
On Monday, authorities said they had rescued 75 crew members, but 31 were still missing in rough seas.
“It’s been more than 12 hours, but we will keep looking,” a navy spokesman told the BBC.
Search crews worked through the night to find survivors, with the operation continuing on Monday with air force assistance.
The navy also announced an investigation into the cause of the disaster.
“This has almost never happened in our force’s history, especially to a ship that is still in active use,” spokesman Admiral Pogkrong Monthardpalin told the BBC.
Officials said the ship went down after it took on water, which flooded its hull and short-circuited its power room.
Writing by Muzha Kucha; Tersoo Nicholas