Suspected attacker detained after St Petersburg supermarket bombing

The suspected bomber of a supermarket in St Petersburg has been detained, Russian media reported on Saturday, citing the country's secret service.

The suspect is thought to have carried out the bomb attack at a Perekryostok supermarket in Russia's second-largest city on Wednesday, in which several people were severely injured.

The individual was arrested on Saturday and taken in for questioning, the state-run TASS new agency reported. No further details were given.

The blast, which apparently came from a luggage locker at the shop entrance, is believed to have been caused by a device that contained shrapnel and had the power of about 200 grams of TNT.

The Islamic State terrorist militia claimed responsibility for the attack on Friday.

Unverified CCTV footage posted online in the wake of the attack appears to show a young man entering the supermarket with a blue rucksack and then leaving without the bag.