This crime has nothing to do with Islam. It's an example of what happens when people with low regard for humanity achieve positions of power. The rapists were militia members, the girl's family complained, the militia used Islam as a smokescreen to "punish" the girl. Their real message was simply "We're in charge and we'll do anything we damned well please. Don't like being raped? See how you like being dead." If they weren't nominally Islamic, they would probably have killed the girl anyway. Their "religion" simply gave them a way to do so in a spectacular fashion that allowed them to get their message across to thousands instead of just a handful.