Assailants burst into a large concert hall in Moscow on Friday and sprayed the crowd with gunfire, killing over 60 people, injuring more than 100 and setting fire to the venue in a brazen attack just days after President Vladimir Putin cemented his grip on power in a highly orchestrated electoral landslide. Moscow Concert Hall Shooting: At Least 60 Dead, Over 145 Injured After Heavy Firing at Entertainment Venue in Russia's Kransogorsk; Islamic State Group Claims Responsibility (Watch Video).