Blast Injures Ten in St Petersburg Shop, 50 Evacuated (PHOTO, VIDEO)

An emergency services' source told Sputnik that 10 people have been injured as a result of "an explosion of an unidentified device" in a shop in the Russian city of St. Petersburg, which has prompted the evacuation of at least 50 people.

According to the Russian Investigative Committee, preliminary data shows that a device stuffed with damage agents is likely to be the cause for the explosion.

"According to the preliminary assessment by explosives experts, an improvised explosive device, equivalent to 200 grams of TNT, exploded in St. Petersburg. The device was filled with projectiles," the press service said.

The Russian Investigative Committee's spokeswoman Svetlana Petrenko told Sputnik that investigators would verify all possible causes of the explosion.

The blast reportedly occurred inside a locker in a grocery store at an entertainment complex.

The police, bomb-disposal experts and rescuers have arrived at the scene; there has been no fire as a result of the explosion, and the building hasn't been damaged much, the source said.

"At the moment the store is closed, buyers and staff have been evacuated. Special services are working at the scene. There is no more detailed information at the moment," the press service of the retail chain told Sputnik.

The Russian Investigative Committee launched a criminal investigation after the explosion, while its head, Alexander Bastrykin, has departed for St. Petersburg in order to examine the circumstances of the blast.

Nine people have been taken to hospitals, the city's deputy governor's office spokesperson told Sputnik.