A Maritime Self-Defense Force minesweeper sank off Fukuoka Prefecture early Monday after catching fire a day earlier, leaving one crew member missing and another injured, the MSDF said.

The fire erupted in the Ukushima minesweeper’s engine room, MSDF officials said, with a 33-year-old petty officer third class believed to have been trapped there. The ship capsized early Monday, sinking later that morning about 2 kilometers north of Oshima, an island in the city of Munakata.

The MSDF and the Japan Coast Guard are working together to search for the missing sailor. That search continued on Monday, with divers taking part.