Deadly Attacks In Russia's Dagestan Raise New Security Questions

The attack on the Crocus concert hall outside Moscow was the deadliest in Russia for almost 20 years (Credit: AFP)

As Russia reels from a spate of deadly shootings by armed extremists for the second time in just over three months, questions have swirled over how the Kremlin's powerful security forces failed to prevent the attacks.

Some pro-Kremlin officials suggested Ukraine and the West were somehow linked to Sunday's violence in the southern Dagestan region, in which gunmen opened fire on churches and synagogues, killing 20 people.