security at the winter olympics will continue to be an overriding concern for the emelin. kremlin.ready employed more than 30,000 troops and security personnel in to the region in an attempt lock down these winter olympics. in an internet video earlier this year, the leader of russia's muslim separatist rebels urged his support toers use maximum force to disrupt the sochi games. he said he was canceling what he called his moratorium on attacks inside russia and warned of new violence. his group claimed responsibility for attacks, including the 2010 moscow underground attack that killed 40 people. and just two days ago, a car bomb killed three people in the southern russian city. as the violence continues to claim lives, ordinary russians may well be wondering where the next attack will come. peter sharp, al jazerra in moscow. >> and at this hour there are conflicting reports as to whether that suicide bomber was a man or a woman. fred joins us now live from moscow, he's the moscow correspondent for the christian science monitor. fred, we know who is behind the attack, at least we b