On March 29, 2010, two female suicide assailants blew themselves up at two separate locations along Moscow's underground network, killing at least 39 people. Two days later, the leader of the rebel movement in the Northern Caucasus, Doku Umarov, claimed responsibility for the attacks. For those monitoring the political situation in the Northern Caucasus, Umarov's claim of responsibility came as no surprise. Even so, few analysts have been able to shed any meaningful light on Umarov's core political beliefs. This is not surprising considering that so much of Umarov's background remains shrouded in uncertainty.