Context : Nur-Pashi Kulayev (born 1980), a native of Engenoi, Chechnya, is thought to be the sole survivor of the 32 hostage-takers in the 2004 Beslan school hostage crisis, although Chechen warlord Shamil Basayev denied the claim, stating that one other escaped. 
Question : Which crime led to the conviction of Nur-Pashi Kulayev?
Beslan school hostage crisis