The fire broke out Thursday night in the regional capital of Urumqi, where temperatures have dropped below freezing after dark.
Flames spread upward from the 15th floor to the 17th floor, with smoke billowing up to the 21st floor, according to multiple state media reports. The blaze took around three hours to extinguish.
The deaths and injuries were caused by inhalation of toxic fumes, with those taken to the hospital all expected to survive, the reports said. An initial investigation appeared to show the fire was sparked by a power strip in a bedroom of one of the 15th-floor apartments.
The fire comes days after 38 people died in a fire at an industrial trading company in central China caused by welding sparks that ignited cotton cloth.
Four people have been detained over the fire Monday in the city of Anyang and local authorities ordered sweeping safety inspections to root out potential dangers.
MNA/PR