With police surrounding hiding place , first suspect kills himself , Russian media say . One of the men arrested reportedly served as an officer in a Chechen police battalion . Four of the five suspects are ethnic Chechens , law enforcement official tells media .
With police surrounding hiding place , sixth suspect kills himself , Russian media say . One of the men arrested reportedly served as an officer in a Chechen police battalion . Four of the five suspects are ethnic Chechens , law enforcement official tells media .