The fire in the residential building has been extinguished, emergency services said.
The natural gas explosion occurred, according to preliminary data, in a five-story residential building in the west of Moscow - three floors were engulfed in fire, a representative of the emergency services said.
Residents are being evacuated with 13 rescued.
Four people were injured in a gas blast, two of them gravely, the city's emergency service said.
Traffic in the vicinity of the burning house in the west of Moscow is blocked, according to the Telegram-channel "Deptrans.Operativno".
"Because of a fire on Kubinka Street, traffic in the area of the emergency is blocked (Kubinka Street, 4) - and is being diverted to the oncoming lanes."