Report: Blast rips through supermarket in Russia's St Petersburg

MOSCOW - A blast ripped through a supermarket in the Russian city of St Petersburg on Wednesday evening, injuring several shoppers, Russian news agencies reported.
Nobody was killed in the explosion, but at least four people were hospitalized and there were unconfirmed reports of a further 10 people being injured.
The cause of the blast was not immediately known, but Russian news agencies reported that investigators had opened a criminal case on the grounds of attempted murder.