In early 2009 , the leader of pan-Caucasian mujahideen , Dokka Umarov , announced the revival of the group as '' ' Riyad-us-Saliheen Brigade of Martyrs ' '' ( without its " Chechen " part of the name , although the group is often referred by media as such anyway ) , saying he has 20 people fully prepared for " martyr operations " . Since then the now much more ethnically-diversified group took responsibility for a series of suicide and other attacks in the Russian republics in North Caucasus and elsewhere , including the 2009 car bombing which killed at least 25 at police headquarters in Nazran , Ingushetia , a car bomb assassination attempt at the Ingush president Yunus-Bek Yevkurov , and the killing of scores of policemen in numerous smaller suicide attacks in Chechnya and Ingushetia , and since the beginning of 2010 eventually also in Dagestan . It also took responsibility for the 2009 Sayano-Shushenskaya hydro accident , was blamed by some for the 2010 Moscow Metro bombings , and has also been alleged to be behind the 2011 Domodedovo International Airport bombing
2009 car bombing
2009 Nazran bombing
Riyad-us Saliheen Brigade of Martyrs