"So far, the main version is household gas," TASS quotes him.
Earlier it was reported that the status of five residents of the house affected by the explosion remains uncertain.
The number of victims, according to the latest data, is 15, including two in serious condition.
Two people were killed.
One of the residents of the house, in an interview with the "360" TV channel, said that after the gas explosion, her family was blocked in the apartment.