Police have said the explosion that killed 16 people at a shopping centre in the northern Russian town of Ukhta was caused by a gas explosion.
The explosion happened in a two-storey brick building.
Ukhta is situated in the Komi region, around 1,500km northeast of Moscow.
Explosions caused by faulty appliances are fairly common in Russia. A gas blast in the city of Arkhangelsk last year levelled an apartment building, killing 58 people.
Any explosion in Russia rattles nerves stretched by attacks linked to Chechen rebels, who have killed hundreds with attacks on Moscow and other Russian cities.
