Meanwhile, in North Africa, a Byzantine–Berber alliance had reconquered Ifriqiya and slain its governor, Uqba ibn Nafi, in the Battle of Vescera in 682. Abd al-Malik charged Uqba's deputy, Zuhayr ibn Qays, to reassert the Arab position in 688, but after initial gains, including the slaying of the Berber ruler Kasila at the Battle of Mams, Zuhayr was driven back to Barqa (Cyrenaica) by Kasila's partisans and slain by Byzantine naval raiders. In 695, Abd al-Malik dispatched Hassan ibn al-Nu'man with a 40,000-strong army to retake Ifriqiya. Hassan captured Byzantine-held Kairouan, Carthage and Bizerte. With the aid of naval reinforcements sent by Emperor Leontios (), the Byzantines recaptured Carthage by 696/97. After the Byzantines were repelled, Carthage was captured and destroyed by Hassan in 698, signaling "the final, irretrievable end of Roman power in Africa", according to Kennedy. Kairouan was firmly secured as a launchpad for later conquests, while the port town of Tunis was founded and equipped with an arsenal on the orders of Abd al-Malik, who was intent on establishing a strong Arab fleet. Hassan continued his campaign against the Berbers, defeating them and killing their leader, the warrior queen al-Kahina, between 698 and 703. Afterward, Hassan was dismissed by Abd al-Aziz, and replaced by Musa ibn Nusayr, who went on to lead the Umayyad conquests of western North Africa and the Iberian Peninsula during the reign of al-Walid.