No less than 10 people have been killed with scores injured after the double explosions that occurred at the Sennaya Ploshchad station in St Petersburg, the centre of Russia’s second city.
The explosions took place at about 2.30pm (11.30am GMT), reportedly as the train was pulling out of the station.
Dmitry Peskov, spokesman of President Valdimir Putin, said his principal visited the city earlier on Monday, but that he was now in the nearby city of Strelna.
“I have already spoken to the head of our special services, they are working to ascertain the cause,” Peskov said, at a meeting with Belarus President Alexander Lukashenko.
Also speaking, Andrei Kibitov, spokesman for the St Petersburg governor, told Russian television that 10 people had been killed and 50 injured in the blast.
The news agency Interfax quoted law enforcement sources claiming the blast was caused by explosive material placed in the carriage.
About an hour after the blast, Putin expressed his condolences to families of the victims before a meeting with the Belarus president, Alexander Lukashenko.
He said it was “too early to say” what caused the blast but that it could be “criminal or terrorist”. Putin said he had already spoken with the director of the FSB security services and other law enforcement agencies.
Photographs from the scene showed a metro train in the station with one set of doors blown out, and a number of people on the ground with injuries.
No group has claimed responsibility for the attacks.