The tentative balance between the different ethnic groups within the Fatimid army collapsed as Egypt suffered an extended period of drought and famine. Declining resources accelerated the problems among the different ethnic factions, and outright civil war began, primarily between the Turks under Nasir al-Dawla ibn Hamdan and Black African troops, while the Berbers shifted alliance between the two sides. The Turkish forces of the Fatimid army seized most of Cairo and held the city and Caliph at ransom, while the Berber troops and remaining Sudanese forces roamed the other parts of Egypt.