River. Another expedition against Ibn Khazar failed to capture the Zenata chieftain. Then, in 932, Ibn Abi'l-Afiya defected to Abd al-Rahman III. As Halm writes, "with this, Fatimid rule over the far west collapsed with one blow", and the territories held by Ibn Abi'l-Afiya and Ibn Khazar became an Umayyad protectorate. The governor of Tahert, Hamid ibn Yasal, was immediately sent west to restore Fatimid control. He managed to defeat Ibn Abi'l-Afiya and reoccupy Fes, but this was ephemeral: shortly after the Fatimid troops left the city, it was lost again, and Hamid was imprisoned at Mahdiya for his failure. Ibn Abi'l-Afiya returned to Umayyad allegiance, but was soon after killed by the Idrisids. North: Sicily and Italy Along with Ifriqiya, al-Mahdi inherited the island of Sicily from the Aghlabids, which had gradually been conquered from the Byzantine Empire during the previous decades. Some Byzantine strongholds remained in the mountainous northeast of the island (the Val Demone), as well as a Byzantine province across the Strait of Messina in Calabria. Sicily was the centre of a perennial war with the Byzantines, which was important from an ideological and propaganda perspective, allowing the Fatimids to "appear as champions of the " against the old Christian enemy of the Muslim world, as the historian Yaacov Lev puts it. At the same time, Lev stresses that the Fatimids were interested more in raiding than outright conquest, that for the Byzantines this was a secondary front, that the fleets involved were small, and that periods of hostility frequently alternated with truces and "a practical policy of modus vivendi". Revolts in Sicily In August 910, al-Mahdi sent his governor of Kairouan, al-Hasan ibn Ahmad ibn Abi Khinzir, as the first Fatimid governor to Sicily. Soon he had made himself so unpopular with the Sicilians, apparently due to heavy taxation—Shi'a jurisprudence entailed a 20% income tax known as the 'Fifth' ()—that they rose in revolt, imprisoned him, and asked for his replacement. His replacement, the elderly Ali ibn Umar al-Balawi, arrived in August 912, but he too was deposed in early 913, and the island rose in revolt under the Aghlabid Ahmad ibn Ziyadat Allah ibn Qurhub, who renounced Fatimid allegiance and received recognition from the Abbasid caliph. In July 914, the Sicilian fleet, commanded by Ibn Qurhub's younger son Muhammad, raided the coasts of Ifriqiya. At Leptis Minor, the Sicilians caught a Fatimid naval squadron