Friday's massacre at a Moscow concert hall, in which at least 137 people were killed, was the deadliest attack claimed by the Islamic State (IS) jihadist group in Europe. - Paris attacks, 130 dead - The worst attack in France's post-war history is carried out by a group of French and Belgian IS gunmen and suicide bombers, who kill 130 people at the Bataclan concert hall, in bars and restaurants, and at the Stade de France stadium on November 13, 2015.