SAINT-PETERSBURG, RUSSIA - APRIL 3: Police officers take security measures near the area after an explosion at a subway station in St Petersburg, Russia on April 3, 2017. A blast hit a train carriage between Sennaya Ploschad and Tekhnologichesky Institut stations of the St Petersburg Underground on April 3, 2017, killing at least 10 and injuring 47 people. (Photo by Sergey Mihailicenko/Anadolu Agency/Getty Images)
