[HIGHLIGHTS] Attack in Moscow: Islamic State published an image of the four alleged perpetrators

Islamic State releases image of four alleged perpetrators of Moscow attack. They appear with half their faces covered, wearing a cap and in front of a large flag of the terrorist group.

At least 133 people were killed in the attack on a concert hall on the outskirts of Moscow. Russian president Vladimir Putin compared the shooters to Nazis and declared March 24 a day of mourning throughout the country. Putin did not name ISIS, but spoke of a terrorist attack, despite the fact that a faction claimed responsibility for the attack.