son Umar, who rebelled in late 869 and massacred the populace of Esna. In winter 870 he defeated an army sent against him by Ibn Tulun, but was driven to the oases of the desert in spring. He remained there until he was defeated in a struggle with another regional strongman, Abu Abdallah ibn Abd al-Hamid al-Umari in 872, fleeing to Mecca. There he was seized and imprisoned for a while by Ibn Tulun. One of his followers, Abu Ruh Sukun, rebelled in the oases in 873/4 and was successful enough for Ibn Tulun to offer him an amnesty. Ibn al-Sufi's vanquisher, al-Umari, was another descendant of Ali who had created an autonomous principality around the gold mines, defeating the forces sent against him. Another revolt broke out in 874/5 by the governor of Barqa, Muhammad ibn al-Faraj al-Farghani. Ibn Tulun tried to reconcile with him at first but was eventually forced to send an army to besiege and storm the city, although the reprisals were limited. The re-imposition of his authority over Barqa, however, led to the strengthening of ties with Ifriqiya to the west, including, according to Ibn al-Athir, the erection of a series of lighthouses and messaging beacons along the coast. In the meantime, in Palestine, the local governor, Isa ibn al-Shaykh al-Shaybani, had used the anarchy in Iraq to set up a quasi-independent Bedouin regime, intercepting the tax caravans from Egypt and threatening Damascus. When Caliph al-Muhtadi ascended the throne in July 869, he offered a general amnesty, and wrote to Ibn al-Shaykh, offering a pardon in exchange for him handing over the treasure he had wrongfully appropriated. When Ibn al-Shaykh refused, the Caliph ordered Ibn Tulun to march against him. Ibn Tulun complied and began a mass purchase of black African () and Greek () slaves to form an army over the winter of 869/70, but no sooner had he arrived at al-Arish with his army in summer 870 than orders came to turn back. Ibn al-Shaykh's revolt was crushed soon after by another Turkish soldier, Amajur al-Turki, who continued to govern Syria for the Abbasids until his death in 878. This episode was nevertheless of major importance as it allowed Ibn Tulun to recruit an army of his own with caliphal sanction. The Tulunid army, which eventually grew to reportedly 100,000 men—other sources give a breakdown of 24,000 Turkish and 42,000 black African and