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.

Paramilitary forces turned El Fasher’s last functioning hospital into a “human slaughterhouse,” massacring hundreds of people including patients as they stormed the city, aid workers and local officials say.