Probe into gas blast at Achinsk refinery in the Krasnoyarsk region.
'The fate of three people is currently unknown'. Picture: Yulia Lebedeva, Channel 7 Krasnoyarsk
Seven other victims were hospitalised as a result of the tragedy which saw a fire sweep through the oil refinery.
'As a result of the fire five people were killed,' the Investigative Committee said in a statement. 'The fate of three people is currently unknown'.
The Siberian refinery is owned by state oil giant Rosneft.
The refinery processes 140,000 barrels a day and the blast was in a 'fractionation unit'.
Tributes to the dead and prayers for the 34 injured including 27 students, acrobats with a Nefteyugansk sports club.
Stunning apocalypse scenes, as night turned to day in southern districts of the Republic of Khakassia.
Acrobats from a sports club were killed after driver lost control in poor weather and hit oncoming truck.
His whiskers were caked in frost after he had sheltered for warmth under a car in the Urals city of Zlatoust - video.