Nail bomb kills at least ten and injures 50 on St Petersburg metro after 'terrorist' places briefcase onto train moments before shrapnel rips through carriages on the day Putin visits the cityhttp://www.dailymail.co.uk/news/article-4375518/Explosion-metro-St-Petersburg.html The horrific blast occurred between Sennaya Ploshchad and Sadovaya train station in St Petersburg, Russia
Ambulances raced to the scene of the carnage caused by a nail bomb which were detonated on the network
Metro officials reported blast was from an improvised explosive device on board which included shrapnel
At least 12 people are reported to have been killed by the blast and 50 including children have been injured
