A group of five teenagers died when a fire broke out as they were playing in an escape room to celebrate one of their birthdays.

Authorities in the northern Polish town of Koszalin said the blaze, which also left a man injured, began on Friday evening.

The group of girls had started the escape room game to celebrate one of their birthdays, Monika Kosiec, a police spokeswoman said. All of them were 15-years-old.

Their bodies were discovered by firefighters as they tackled the blaze, the spokeswoman added.

She also said the injured man, who was aged 25, had been sent to hospital suffering from burns and was not yet well enough to be questioned by fire investigators.

Ambulances and fire engines were filmed by local TV stations outside a detached two-storey house with a large Escape Room sign outside in Koszalin, a city of 100,000 near Poland’s Baltic Sea coast.

The head of Poland's fire brigade, Leszek Suski, said on Saturday electrical wiring and lax security procedures were to cause for the deadly blaze.

The fire began in a room next door to where the girls had been locked in while they played the game and they are believed to have died of carbon monoxide asphyxiation.

Mr Suski said the wiring in the facility was makeshift and far too close to easily flammable material and the person in charge of the escape room was probably not present when the fire broke out.

Poland's president, Andrzej Duda said on Twitter it was a “crushing tragedy” the five girls had died so early in their lives.

“Five joyful girls starting out in life have had life torn away from them. May God protect their parents and loved ones," he wrote.

A day of mourning for the city would be held on Sunday, the mayor, Piotr Jedlinski, announced.

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Poland's interior minister, Joachim Brudzinski, has also ordered the fire brigade to make checks on all escape rooms across Poland and where necessary install fire safety controls.

Games where people are locked inside a room and must uncover clues and solve riddles to escape within a time limit have become highly popular in recent years, particularly among teenagers.