Update 11am: Polish firefighters have blamed poor electrical wiring and lax security procedures at an Escape Room for a fire that killed five teenage girls and injured a man.
The bodies of the 15-year-old victims were found on Friday in Koszalin, in northern Poland, after firefighters put out a blaze in an adjacent room.
Asphyxiation is the probable cause of the deaths, officials said.
Poland's firefighting chief, Leszek Suski, said that electrical wiring at the location was makeshift and too close to flammable materials, while the man in charge was probably not there when the fire broke out.
The Escape Room game sees players locked inside a room or building and they must find clues that help them get out.
Prime Minister Mateusz Morawiecki has sent condolences to the victims' families.
Five teenage girls have been killed and one man hurt in a fire that broke out at an Escape Room game location in northern Poland, officials have said.
The country's interior minister Joachim Brudzinski said the girls were all 15 years old.
A police spokeswoman in the city of Koszalin, Monika Kosiec, said the victims were probably celebrating one of their birthdays.
A 25-year-old man has been taken to hospital with burns and could not be immediately questioned by investigators who are probing the cause of the fire, she said.
Ms Kosiec said the bodies were found after firefighters put out a fire that broke out at the location.
Polish news agency said it learned unofficially that the victims died from carbon monoxide asphyxiation.
Mr Brudzinski ordered fire safety controls in all Escape Rooms, which are very popular with teenagers across Poland.
In an Escape Room game, the players are locked inside a room or building and must find clues that help them get out.
President Andrzej Duda said on Twitter it was a "crushing tragedy" that five young girls died so early in their lives.
Koszalin mayor Piotr Jedlinski announced that Sunday would be a day of mourning in the city.
- Press Association