At least 15 people were killed in a fire at a bar in the Russian city of Kostroma on Saturday, Russian news agencies reported.

The night’s fire at the popular bar may have been started after a drunk man fired a “flare gun” at the dance floor, the TASS news agency reported.

State television showed images of the bar – dubbed “Poligon” and housed in a one-story logistics center – bursting into flames.

According to authorities, the fire started around 2:00 a.m. local time and was extinguished around 7:30 a.m.

Governor Sergei Sitnikov previously said 13 people were killed, but emergency services then said the remains of two others had been found.

“Two other bodies were recovered. This means the number of victims is now 15,” TASS news agency quoted law enforcement sources as saying.

Around 250 people were evacuated from the building when it caught fire in the city about 300 kilometers northeast of Moscow, authorities said earlier.

The TASS news agency, citing emergency services sources, said a drunk man with a “flare gun” likely caused the fire.

“He was hanging out with a woman in the bar, ordering her flowers, with a flare gun in hand,” the agency source said.

“Then he went onto the dance floor and fired it.”

Local emergency services said the fire had spread over 3,500 square meters.

On its website, Poligon says it functions as a “place for recreation and entertainment” in the evenings and nights.

During the day it’s a typical Russian “Stolovaya” – a casual restaurant with traditional cuisine.

It is said to be housed in a “distribution center” and popular with the traffic police.

State television showed images of dozens of responders battling a massive blaze that had engulfed the one-story building.

The sign “Poligon” could be seen amidst the flames raging on the roof.

A firefighter told regional state television that it took 50 people to put out the fire and that they deployed 20 fire engines.

He said the fire was particularly difficult to put out because of the risk of the building collapsing.

Kostroma, a city on the Volga with around 230,000 inhabitants, is one of the oldest cities in Russia and is famous for its medieval architecture and monasteries.