Rescuers in southern Japan spotted wreckage believed to be connected to a sightseeing helicopter that went missing near Mount Aso with three people aboard, authorities said Wednesday.

The helicopter lost contact during what was expected to be a scenic 10-minute flight over Mount Aso on Monday, according to a flight operator and local authorities.

On Tuesday, local police said wreckage, possibly from the missing helicopter, was spotted inside the crater of Nakadake, one of Mount Aso’s five peaks. Fire department officials said strong winds and volcanic gases hampered the rescue operation.

Takumi Morioka, head of the helicopter tour operator Takumi Enterprise, said during a news conference Wednesday that the pilot and the two passengers were unaccounted for and that he hoped they survived.

The company previously said that last year, a helicopter operated by it made an emergency landing while flying over the same volcano, injuring three people on board.

Volcano viewing helicopter tours around Mount Aso, which last erupted in October 2021, are among popular tourist attractions in Kumamoto prefecture in southwestern Japan.