At least 10 people have died and more than 20 were injured in a blast in Russia's St Petersburg. The blast had taken place in a carriage of a running metro train around 2.40 pm local time, reported Russian news agencies. News channel Russia Today reported that President Vladimir Putin has said all possible causes of the explosions in the St. Petersburg Metro are being considered, including those linked to terrorism. President Putin had come to St Petersburg for a meeting. Hunt is on for a suspect who has been seen on CCTV footage.
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Quoting the National Anti-terrorism Committee, Russia Today reported that the explosion took place as the train was travelling between the stations Tekhnologichesky Institut and Sennaya Ploshchad.
The police also suspect that the explosion was caused by an Improvised Explosive Device or IED, which was hidden in a suitcase.
Another explosive device had been found at a different metro station, hidden under a fire extinguisher, but had been defused, said Russia's National Anti-Terrorist Committee.
Russian news media reported that police were searching for a man recorded on surveillance cameras who was thought to have been involved in the attack. The middle-aged, bearded suspect is seen wearing a black hat, said Fontanka news outlet.
All subway stations of St Petersburg were closed after the explosion. Commuters were evacuated minutes after the blasts were reported.
Video footage showed graphic images of smashed train doors and injured people on the platform. A huge hole has been blasted on the side of one carriage, mangled metal wreckage is seen strewn around the platform.
Passengers were seen hammering at the windows of a closed carriage.
With concerns of a potential follow-up attack, security has been tightened across St. Petersburg.
The Moscow metro said it was taking additional security measures in view of a possible attack there.
Chechen militants have carried out attacks in Russia earlier. In 2010, at least 38 people died when two women suicide bombers detonated bombs on packed Moscow metro trains.
