At least 10 people have been injured by the blast on Monday morning, the report said. Police are currently at the scene investigating the cause of the incident.
Russia’s Investigative Committee believes the explosion could have been a new terrorist attack.
The new deaths come just a day after a suicide bomber targeted the city’s railway station, killing 14 people on the spot and injuring more than 30 others. Three of those injured succumbed to their wounds in hospital.
And in October the city witnessed yet another terrorist attack, when a suicide attacker set off an explosion in a bus heading to Moscow, killing 6 people and injuring almost 40.
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