The minesweeper JS Ukushima, seen here in an undated photo, caught fire and eventually sank on November 11, 2024. (Japanese Ministry of Defense)

TOKYO — A joint US-Japan naval exercise has been canceled after a Japanese sailor went missing following a weekend fire aboard a minesweeper that eventually sank.

The US and Japanese navies were scheduled to conduct mine training between Saturday and Tuesday until the JS Ukushima caught fire on Sunday and sank the following day. The ship’s crew was training en route to the joint exercise, a spokesman for the Maritime Self-Defense Force told Stars and Stripes by phone Tuesday.

The exercise was canceled because of the effort to find Petty Officer 3rd Class Tatsunori Koga, 33, who was working in the ship’s engine room, the command said in a news release.

Another sailor working in the same room was injured; the remaining 43 crew members were safely evacuated, the spokesman said. In Japan it is customary for some government officials to speak to the media without naming themselves.

The fire broke out around 9:45 a.m. Sunday in waters 1½ miles north of Oshima in Fukuoka Prefecture, part of Kyushu, the southernmost of Japan’s four main islands. It was extinguished around midnight on Monday, but the vessel finally sank at around 8:34 a.m., the spokesman said.

Ukushima was built with a wooden hull, according to the spokesman.

Japan’s Maritime Self-Defense Force and Coast Guard were still searching for Koga on Tuesday afternoon.

The fire is believed to have started in the engine room, where the ship’s diesel engines are located, Chief Cabinet Secretary Yoshimasa Hayashi told a news conference on Monday.

“The Japanese government will do its best to search for the missing personnel and take all possible measures to determine the cause and take preventive measures,” he said.

The Self-Defense Force has set up a committee to investigate the cause of the fire, Hayashi said.

The US 7th Fleet confirmed an email from Stars and Stripes asking if the US would help with the search or continue the exercise. The command did not respond by closing time on Tuesday.