Answer
Al-Hajjaj ibn Yusuf was dispatched by Abd al-Malik to eliminate Ibn al-Zubayr. Al-Hajjaj, a skilled general, besieged Mecca, where Ibn al-Zubayr had established his caliphate. After a prolonged siege, al-Hajjaj's forces breached the city, and Ibn al-Zubayr was killed in the ensuing battle. This victory solidified Abd al-Malik's control over the Umayyad Caliphate and ended the challenge posed by Ibn al-Zubayr.