The UN High Commissioner for Human Rights Navi Pillay has called on Nigerian political and religious leaders to join together in efforts to halt sectarian violence in the country. In a statement yesterday, Pillay said it is especially important for Muslim and Christian leaders to “condemn all violence,” including retaliatory attacks. She said those efforts could help stop a dangerous situation from “spiralling out of control.” Her comments come a day after the leader of the militant group Boko Haram promised more attacks. Nigerian authorities blame Boko Haram for hundreds of deaths in bombings and shootings over the past 18 months. The group has claimed responsibility for several of the attacks, including a Christmas Day bombing of a church near Abuja that killed more than 30 people. Pillay said if Boko Haram members are judged to have carried out systematic attacks against civilians, then the militants could be found guilty of crimes against humanity.