An explosion has hit St Petersburg’s metro system, with at least 10 people killed and many injured.
The Russian state prosecutor’s office said in a statement that an investigation was under way after an explosion on a train that was on the platform at the Technological Institute station in the centre of Russia’s second city.
But shortly after that the country’s national anti-terrorism unit said the explosion occurred on a train running between the Technological Institute and Sennaya Square stations.
A second bomb was later found at Insurrection Square station. The “self-made unexploded explosive device” had been detected and defused as the security services started their investigation of the crime scene, the National Antiterrorism Committee said.
President Vladimir Putin said he had already been in contact with the emergency services, which are “doing all they can to determine the reasons” for the incident, and that support was being offered to families of the victims.
Social media users posted photographs from one subway station in the city centre, showing people lying on the floor and a train carriage with a mangled door and windows blown out in the background.
The regional government’s press service said 50 people had been injured.
“According to preliminary data, as a result of the blast ten people died. The governor is at the scene,” said Andrei Kibitov, spokesman of Georgy Poltavchenko, governor of St Petersburg.
The blast occurred while Mr Putin was meeting in St Petersburg with members of the All-Russian People’s Front, a mass organisation which he founded and heads, and as Belarusian president Alexander Lukashenko was visiting the city.
Police have not yet commented whether a terrorist attack is suspected.
“Unfortunately, we must begin our meeting with this tragic incident,” Mr Putin said in a meeting with Mr Lukashenko. “The reasons are still unclear, therefore it is still early to speak about that. But of course we always look at all possibilities – technical as well as criminal and, above all else, manifestations of a terrorist nature.”
Viktor Ozerov, head of the committee on defence and security in the Federation Council, Russia’s upper house of parliament, said: “Of course all signs of a terrorist act are there.”
The blast comes as Mr Lukashenko is battling continued political unrest and Mr Putin is also facing renewed street protests.
The incident is the first explosion with casualties in Russia’s second-largest city since 2007. While the restive North Caucasus region has seen several violent attacks in recent years, there have not been any terrorist attacks in Russia’s heartland since a series of deadly bombings in the Southern city of Volgograd in December 2013.