A Japanese married couple died earlier this month after they became trapped in their private sauna at Sauna Tiger, in the Akasaka district of Tokyo.
Tokyo police are reportedly investigating what led to the couple becoming trapped in the sauna, suspecting the unit had a faulty doorknob, local media reported.
In addition to suspecting a faulty doorknob, investigators found that Sauna Tokyo’s emergency alarm system had been switched off for at least two years prior to the incident.
"We offer our deepest condolences... and our heartfelt sympathies for the deep grief and pain that cannot be expressed in words," Sauna Tiger said in a statement on its website.
Local media named the victims as 37-year-old Yoko Matsuuda and 36-year-old Masanari Matsuda.
The fire department responded to the call around midday after Sauna Tiger’s fire alarms went off. Upon arriving at the facility, the firefighters found the doorknob of one of the saunas on the floor, according to Japanese media.
The couple was found on the floor, lying on top of one another with their heads near the door, according to local media. Despite being rushed to hospital, they both later died.
A burnt towel was discovered in the sauna, which police said they believed may have caused the fire. The towel, they theorized, could have touched the hot stones and caught alight.
Police found the emergency alarm’s cover had been removed, indicating that the couple had likely attempted to call for help, the Metropolitan Police Department said.
Staff later claimed during questioning that the alarm had not been switched on “since around 2023,” police said.
Sauna Tiger, which started operations in the summer of 2022, was inspected in April 2023. The inspection found “no major deficiencies” in the equipment, the Minato Public Health Centre told The Asahi Shimbun newspaper.
In its statement, Sauna Tiger said it was taking the incident "very seriously" and "cooperating fully with the investigations by the fire department."