"As of 08:00 (on December 28, 2017), the total number of people injured in the blast in a supermarket in Kondratyevsky Avenue is 13. Of these, five refused to be taken to hospital. Five of those remaining in hospitals are in a moderately grave condition, while three are in a satisfactory condition," Russia's news agency TASS reported, citing the city's Vice-Governor in charge of social issues, Anna Mityanina, as saying, in a Twitter post.
The incident, which occurred at the Perekrestok supermarket late on Wednesday, is being investigated as a "potential mass homicide attempt," the officials said.
Earlier reports had stated that the incident left ten persons dead.
There are reportedly no children among those injured.
The explosion went off inside a locker of a grocery store. (ANI)