A "drunk man" fired a "flare gun" in a bar in Russia, sparking a blaze that killed 13 people, injured five and triggered the evacuation of hundreds, according to local authorities.
The fire broke out in the city of Kostroma in the early hours of Saturday morning after a man reportedly shot a distress flare at the dancefloor in the Poligon bar.
Russian state-owned news agency Tass reported that "the fire was likely started by a drunken man who fired a distress flare at the dance floor."
"He was at the bar with a woman, to whom he offered flowers with a distress flare in his hands. He went to the dance floor and shot," it added, citing the emergency services.
Police said they arrested the suspected perpetrator on Saturday.
Rescuers evacuated 250 people from the Poligon, a dance bar and restaurant located in a warehouse, which AFP initially reported as a cafe.
Governor of the Kostroma region, Sergei Sitnikov, said five people were slightly injured and received medical assistance.
The roof of the cafe collapsed during the blaze, which emergency services said started at around 2 am local time and spread over an area of 3,500 m2.
It was put out early Saturday morning, with 20 fire engines and 50 firefighters tackling the flames.
After a short search for the alleged perpetrator, the Russian Interior Ministry said it had "identified and arrested a suspect for an illegal act in one of the night bars in the city of Kostroma, which caused a fire and the death of victims".
They did not give any more details about the man.
A criminal investigation was immediately launched by the Russian Investigative Committee, the main investigations unit in the country.
"Investigators" and "medical examiners" attended the scene, it said.
On its website, the Poligon describes itself as a traditional Russian brasserie by day and a dance bar by night. The venue is very popular with traffic policemen, it says.
Kostroma, home to 230,000 people, is located roughly 340 kilometres north of Moscow.
It is one of the oldest cities in Russia, renowned for its medieval architecture and monasteries.
This is not the first time pyrotechnics have sparked a deadly fire in Russia.
In 2009, more than 150 people were killed in a blaze at the Lame Horse nightclub in the city of Perm that erupted after someone set off fireworks.