Firefighter chief Leszek Suski said the escape room at a private house in the city of Koszalin, where the girls died Friday locked inside a room celebrating a birthday, had no emergency evacuation route. Firefighters found the bodies of the 15-year-old victims after they extinguished a fire next to the locked room. Autopsies showed they died of carbon monoxide inhalation.
Source: latimes.com – Los Angeles Times