WARSAW, POLAND: Prosecutors in northern Poland detained and brought charges Sunday against the man who designed an escape room entertainment site where five teenage girls were killed in a fire.

The man, identified only as Milosz S., was charged with intentionally creating a fire danger and unintentionally causing the deaths of the girls, said prosecutor Ryszard Gasiorowski, adding that the location’s heating system was faulty and there was no emergency evacuation route.

A court decision is expected Monday on prosecutors’ request that he be held for three months while the case proceeds.

Firefighters in the city of Koszalin found the victims’ bodies Friday after they extinguished a fire next to the locked room. Prosecutors say a leaky gas container inside a heater is the most likely cause of the blaze.

Autopsies showed that the girls, who were friends from school, died of carbon monoxide inhalation. A young man employed there was hospitalized with burns. He was to be questioned.

Attorneys for the man charged said he was “deeply distraught” by the deaths and has expressed deep condolences to the families before the prosecutors. They said the 28-year-old denies the charges but because of his distress was not able to answer prosecutors’ questions. If convicted, he could face up to eight years in prison.

Earlier Sunday, fire chief Leszek Suski stressed that the escape room at a private house in the city of Koszalin, where the 15-year-old girls died locked inside a room celebrating a birthday, had no emergency evacuation route. They were the first known deaths in an escape room, a form of entertainment that has been growing in Poland over the past five years.

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. Regarded as an intellectual challenge, the games are highly popular among teenagers in Poland.

Officials have shut down 13 escape room entertainment sites for safety flaws and the prime minister asked people Sunday to report such lapses to firefighters and police.

Police chief Jaroslaw Szymczyk said other people had previously posted critical remarks online about the safety of that escape room site, but local officials weren’t notified.

During a memorial Mass at Koszalin Cathedral, Bishop Edward Dajczak identified the girls by their first names as Julia, Amelia, Gosia, Karolina and Wiktoria.

He later led public prayers in front of the house where they died. People left hundreds of lights, toys and white flowers by the fence.

Prime Minister Mateusz Morawiecki, along with Suski and Szymczyk, spoke after holding a meeting in which they discussed with other officials ways of improving safety at entertainment venues. Morawiecki called the girls’ deaths an “immense tragedy.”

Since Friday, more than 200 of Poland’s 1,100 escape rooms have been checked, revealing a number of safety flaws that needed to be immediately fixed. Authorities ordered the closure of 13 of them.