maiduguri nigeria nigeria replace military commander fight boko haram half year army spokesman say wednesday follow string insurgency attack despite years official claim group almost defeat shake-up underscore fragility security situation nigeria northeast conflict islamist insurgent group ninth year despite assertions president muhammadu buhari administration last legs military spokesman confirm replacement ibrahim attahiru theater commander operation boko haram text message reuters major general rogers nicholas take position spokesman provide detail attahiru removal come wake series embarrass attack two military source tell reuters say conduct war insurgents review attack occur attahiru command include kidnap members oil prospect team lead least 37 people kill july deadly assault towns magumeri biu madagali source say spokesman president serve nigeria commander-in-chief decline comment governor borno state epicenter insurgency say government long-term plan corral civilians inside fortify garrison towns effectively cede countryside boko haram plan spate deadly attack raise question assertions government military boko haram wipe well doubt nigeria ability retain sovereign integrity northeast nigeria replace commander fight boko haram six months