Five teenage girls have died after a fire broke out while they were playing an escape game in northern Poland.
A man was seriously injured by the fire but survived.
The youngsters perished in the fire that is believed to have started around 5pm local time (4pm GMT), on Friday afternoon. What caused the fire has not been determined.
An escape room is where a group of people are locked inside and try to find a way out by searching for clues as part of a game.
While most of these escape rooms have an evacuation route or escape room employees watching the players from outside the room with a camera, it seems that this was not the case during this incident in Poland.
Five 15-year-old girls have died in a fire in an escape room in Koszalin, Poland.
Officials have said asphyxiation was the probable cause of the deaths, and a gas leak was the most likely cause of the blaze.More news: Swedish hospital isolates patient amid Ebola suspicion - 1/4/2019 7:05:50 AM
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During a memorial Mass at Koszalin Cathedral, Bishop Edward Dajczak identified the girls by their first names as Julia, Amelia, Gosia, Karolina and Wiktoria.
Polish officials and the fire chief have confirmed that there was indeed a safety flaw didn't allow the children to escape from the blaze when the room caught fire.
In "escape rooms", participants are locked in a room and race against the clock to solve puzzles and challenges to open a way out.
Forensic and other police experts examine the site of the fire.
Police spokeswoman Monika Kosiec said the fire was in a room near where the girls were celebrating a birthday party.
Prime Minister Mateusz Morawiecki spoke after holding a meeting in which officials discussed ways to improve safety at entertainment venues.
Koszalin Mayor Piotr Jedlinski announced that Sunday would a day or mourning in the city.