MOSCOW (REUTERS) - A gas explosion ripped through an apartment block and set it ablaze in the southern Russian city of Volgograd on Sunday (Dec 20), injuring at least eight residents while some were feared dead, Russian authorities said.

The Russian Investigative Committee, which reports directly to President Vladimir Putin, said around 150 people lived in the section of the nine-storied house.

Local TV showed footage of firefighters trying to put out the fire, and of the building's heavily damaged facade.

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.

In one of the biggest such incidents, 58 people died in March 2004 in Northern city of Arkhangelsk.