A reported blast at a shopping centre in Saint Petersburg, Western Russia is being investigated as an attempted murder plot after four were taken to hospital and dozens more were evacuated from the building Wednesday evening.

Russian state media reports the leisure centre and supermarket in Saint Petersburg was crowded with “thousands” of shoppers in the run-up to Russian Orthodox Christmas day, which takes place on January 7th.

#BREAKING Blast in supermarket in Saint Petersburg, Russia, several injured: police — AFP news agency (@AFP) December 27, 2017

Four were taken to hospital with injuries after the blast which originated from a storage locker inside the shop, and dozens more were evacuated. Russian state media outlet RT reports the blast is being investigated as a”potential mass homicide attempt” and the explosion was “equivalent to 200g of TNT”.

The state TASS news agency reports “There was a bang. Emergency personnel are already on the scene. The evacuation has been completed, and there was no fire.”

Russia has been on high alert for Islamic insured terror over the Christmas period after the United States’ CIA intelligence agency tipped off Russia’s FSB with intelligence about an Islamic State cell in the country, leading to seven arrests. Explosives and weapons were found during raids, and it is reported the Islamic radicals had been planning to attack St Petersburg over the Christmas period.

A significant number of other Christmas terror attacks by Islamic radicals have been foiled by security services worldwide in recent weeks.

Today’s suspected attack comes on the same day that the disgruntled former owner of a candy factory in Moscow, Russia shot and killed a security guard and injured three others with a shotgun after an argument with the plant’s new owner. Police cordoned off the area (illustrated, above) and entered into a standoff with the gunman.

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