Five teenage girls who died in a fire at an escape room entertainment site in Poland will be buried together in a joint ceremony, the city mayor said.
Fire officials said 26 similar sites have been shut down because of security flaws since Friday's tragedy and inspections of around 1,100 sites across Poland continue.
The man who designed the escape room in the northern city of Koszalin has been detained and charged with intentionally creating a fire danger and unintentionally causing the deaths.
The local court ordered the man, identified only as 28-year-old Milosz S, to be arrested for three months while the case proceeds.
Prosecutors said the site's heating system was faulty and there was no emergency evacuation route.
Koszalin mayor Piotr Jedlinski said the city is arranging and financing the joint burial on Thursday of the 15-year-old victims, who were friends from the same school class and celebrating a birthday when they died.
Prosecutor Ryszard Gasiorowski said an employee at the site who suffered burns and remains in hospital told investigators that one of the gas cylinders in the reception room's heating system began making a strange sound and he could not fix it.
He said the fire started suddenly and cut off his way to the door of the locked room where the girls were.
The employee then ran out of the building and asked passers-by to call for help.
Players in escape room games are locked inside a room or building and must solve puzzles and find clues that lead them to the key that will unlock the door.
The games are highly popular among teenagers in Poland.
In reaction to the tragedy, film distributor United International Pictures' spokeswoman Kinga Zych said it was putting off the January 11 premiere in Poland of US horror movie Escape Room by Adam Robitel.