ABUJA( Reuters)-Armed men killed 15 people in raids in Nigeria's Sokoto state, government officials said, despite a military effort to stamp out a tide of violence in the northwest. Sokoto state Gov.... There is a telecommunications blackout in place across large swathes of the northwest to aid an armed forces crackdown. President Muhammadu Buhari condemned the attack and said the military is deploying advanced technology to track down attackers.... " This persistent and unprovoked violence ag