The Life News website showed pictures of blown-out train doors and injured people on the station platform.
An explosion in the St. Petersburg metro on Monday has left at least nine people dead, according to Russian state media.
At least 50 people have been reported injured from the blast, state media reported.
The St. Petersburg subway press office confirmed an explosive device was set off on a train, according to the Associated Press.
The blast reportedly occurred while a train was moving between two stations — Tekhnologichesky Institut and Sennaya Ploshchad.
Another bomb was found and deactivated at a different St. Petersburg metro station, according to Russian antiterrorism officials. That station, Vosstaniya Square, is about 20 minutes by car from the site of the blast.
Earlier reports had suggested there could be two blasts, but the latest information from Russian news agencies suggests there has been only one.
Here's a look at the aftermath of the blast:
St. Petersburg metro closed all stations in response to the deadly blast.
Russian President Vladimir Putin, who was in St. Petersburg when the blast occurred, said in a statement that authorities were considering all possible motives, including terrorism.
Here's a map of the affected stations:
Various websites and social-media users have posted pictures of blown-out train doors and injured people on the station platform, which appears to be at a stop in the center of Russia's second-biggest city.