A gas explosion has ripped through an apartment block in the southern Russian city of Volgograd, sparking a blaze.
Authorities said at least one person was killed and eight injured in the blast on December 20.
Authorities said five people were unaccounted for and feared dead.
The Russian Investigative Committee, which reports directly to President Vladimir Putin, said around 150 people lived in the section of the nine-storied house where the blast occurred.
Local TV showed footage of firefighters trying to put out the fire.
Gas blasts are relatively common in Russia, where Soviet-era infrastructure is ageing and safety requirements are often ignored.
Just a week ago, a fire swept through a psychiatric clinic in a village in the Voronezh region south of Moscow, killing 23 people.