Ahavuye isanamu, AFP/Getty Insiguro y'isanamu, Si ubwa mbere Bwana Shekau ashikiriza ubutumwa abicishike muri video Shekau - asanzwe arongoye Boko Haram haciye imyaka icumi - yaragiriraniye amasezerano n'umurwi IS mu mwaka wa 2015.
