Diver from Taiwan Dies In Survey Work at Undersea Coal Mine Site Off Yamaguchi Pref.

The Yomiuri Shimbun

19:40 JST, February 8, 2026

A diver died Saturday while he was working on a survey at the Chosei undersea coal mine off the coast of Ube, Yamaguchi Prefecture.

The survey aimed to search for the remains of victims of a flooding accident that occurred at the coal mine beneath the seafloor during the Pacific War, in which 183 workers including ones from the Korean Peninsula lost their lives.

Another person participating in the survey called for an ambulance around noon on Saturday, saying, “A diver had convulsions while diving.” The diver was taken to a hospital, where he was confirmed dead, according to the Ube police station of the Yamaguchi prefectural police.

According to a civil group aiming to recover and return the remains of the victims at the former coal mine site, the diver was a 57-year-old man from Taiwan. To recover the remains of the victims, he and two other foreign divers cooperating with the group entered the water Saturday morning through an exhaust pipe protruding from the surface of the sea 300 meters from shore. The other two divers reportedly noticed that he had convulsions during the diving operation.

The underwater survey began on Feb. 3 and was scheduled to end Wednesday, but the group reportedly plans to cancel the remainder of the survey. In survey work conducted Friday, a bone that seems to be part of a skull was found.