MOSCOW, December 3 (RIA Novosti) - Four people were killed and two others injured when a fire broke out in a sauna in Smolensk, in western Russia, a law enforcement source said on Wednesday.

"Four people died of burns and gas asphyxiation while two others were hospitalized," the source said.

The cause of the fire is believed to be a breach in fire regulations, he said.

A criminal case has been opened. If found guilty of breaching fire regulations the sauna owners could face up to 10 years in jail.