Investigators from the Sverdlovsk region said a child was among those killed and that a criminal case had been opened to determine the cause of the fire and establish measures that could prevent a similar incident in the future.
The fire was reported at 2:58 a.m. local time (2158 GMT on Monday) and contained by firefighters before being extinguished a little over an hour later, the regional emergency services ministry said.
“In conditions of heavy smoke, the gas and smoke protection service organised the evacuation and rescue of residents through a burning doorway,” the ministry said in a statement.
“In total, 90 people, including nine children, were evacuated.”
Video footage showed dozens of firefighters on hand, helping residents to escape the building.