The Sicilian rebel remnant withdrew into the fortified citadel ("qasr") of Palermo (the old center now known as Cassaro), leaving the town and suburbs open to the sack of the Ifriqiyan army. After about a week, on 18 September 900, the Sicilian rebels surrendered, yielding up the Qasr to Abdallah in return for safe-passage of the rebel leaders into exile. Streams of Palerman refugees made their way east to take shelter in the Byzantine holdings. The next year (901), Abu al-Abbas Abdallah led the Aghlabid army against the remaining Byzantine enclaves in Sicily. While laying siege to Demona (in the northeast), Abu Abbas Abdallah heard rumors of the assembly of a Byzantine army in Calabria. Breaking off the siege, he rushed the Aghlabid army up to Messina, and ferried it across the straits, soon appearing before the walls of Reggio Calabria in June 901. Unprepared, the Byzantine garrison abandoned the city. The Aghlabids seized Reggio and put the wealthy city through a thorough sack. Mounting reports of the cruel atrocities of Ibrahim II made their way to Baghdad, prompting the Abbasid Caliph al-Mu'tadid to finally react. The Caliph dispatched a messenger who arrived in Tunis in late 901/early 902 with his written instructions. Citing the mistreatment of his subjects, the Caliph recalled Ibrahim II to Baghdad and deprived him of the governorship of Ifriqiya, appointing in his stead his son Abu al-Abbas Abdallah (then on campaign in Sicily). Surprisingly, Ibrahim II dutifully accepted the news without objection. With apparently genuine repentance, donning the garments of a penitent and declaring a pious change of heart, Ibrahim II remitted tributes, abolished illegal taxes, opened his jails, manumitted his slaves, and delivered a large chunk of his treasury to the jurists of Kairouan to distribute to the needy. Ibrahim II abdicated his power to his son Abu al-Abbas Abdallah, who returned from Sicily in February–March 902 to assume title as the new emir Abdallah II of Ifriqiya. The deposed Ibrahim, however, did not go to Baghdad, as ordered. Instead, he declared himself a "mujahideen", that he would seek to expiate his crimes by pursuing holy war on the Christians.