A Look Back At Major Terror Attacks Under Putin's Rule

Gunmen opened fire at a packed music venue in Moscow on March 22, killing at least 62 people and wounding 100 more, in the worst such attack in Russia in years.

The Islamic State (IS) extremist group claimed responsibility for the attack, in which several gunmen stormed into the popular Crocus City Hall concert venue, where, music fans had gathered for a gig.

Here are some of the other majo