Let me guess.... Muslims.
Unstated is that the fighting pits Muslim African tribals of the west against Muslim Arab tribals of the center-east. After suffering decades of depredations the Africans are getting their revenge. The Arab center (Khartoum-Wad Medani) is either under attack or has fallen to the ‘Rebels’ from the west. The Khartoum (Arab) government is looking to Cairo to save it from total defeat, but thus far Cairo is playing it coy.