Sudanese rebels have driven government forces from El Fasher, the last stronghold of the country’s regime in the western Darfur region, amid a brutal struggle for territory that has led to alleged genocide and contributed to one of the world’s most severe humanitarian crises.

Sudan's brutal two-year war has entered a new, dangerous phase. The paramilitary Rapid Support Forces this week seized control of the entire Darfur region, after ousting the rival Sudanese army from its last stronghold there.