Overview

• The victims, aged in their 50s and 60s, were employees of the Kagetsu Highland Hotel and were performing routine maintenance on February 17.
• Their bodies were discovered on February 18 near a mountain trail, approximately 100 meters from the hotel, after failing to return from their work the previous evening.
• Authorities suspect the deaths were caused by inhalation of hydrogen sulfide, a naturally occurring toxic gas found near volcanic hot springs, though the official cause of death has not yet been confirmed.
• Heavy snowfall in the area, reaching up to 57.5 inches, may have contributed to the accumulation of the gas in depressions formed by melting snow around the hot spring pipes.
• Rescue teams faced hazardous conditions, including high gas concentrations and frigid temperatures as low as -7.7°C, requiring the use of oxygen tanks during their search.