Transcript for Explosion kills at least 10 in St. Petersburg

That's what we know right now. The first images we're seeing from that explosion in St. Petersburg, Russia, today. As I said at least ten people are dead. I want to go to Alex Marquardt. He is in London with the latest. Good morning. Good morning. That's right. We're getting reports of at least ten dead from the state news agency tass happening in central St. Petersburg and there's news of a second explosion at the technological institute and grim pictures of a destroyed subway car and in addition to those killed, many have been wounded. St. Petersburg is Russia's second city. The hometown of Russian president Vladimir Putin who we know is in the city today. There has been no claim of responsibility. But the immediate assumption will fall on islamic extremists from the caucasus and they've gone to fight and Russia is fighting on the side of the Assad regime but for now no sense yet of who or what may be responsible for this. Right. We know president Putin has been briefed and that he was in the city but, of course, he is -- he was not affected by this in any way. Reporter: Yes, there's no indication right now he was affected in any way or that he was a target. This is peers to have been carried out at these two main stations but he was not involved. Alex Marquardt, thanks very much. An explosion and at least ten dead. We'll stay on top of it all morning long but upstairs to

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