In 1632, Al-Mu'ayyad Muhammad sent an expeditionary force of 1,000 men to conquer Mecca. The army entered the city in triumph and killed its governor. The Ottomans were not ready to lose Mecca after Yemen, so they sent an army from Egypt to fight the Yemenites. Seeing that the Turkish army was too numerous to overcome, the Yemeni army retreated to a valley outside Mecca. Ottoman troops attacked the Yemenis by hiding at the wells that supplied them with water. This plan proceeded successfully, causing the Yemenis over 200 casualties, most from thirst. The tribesmen eventually surrendered and returned to Yemen. Al-Mu'ayyad Muhammad died in 1644. He was succeeded by Al-Mutawakkil Isma'il, another son of al-Mansur al-Qasim, who conquered Yemen in its entirety, from Asir in the north to Dhofar in the east. During his reign, and during the reign of his successor, Al-Mahdi Ahmad (1676–1681), the imamate implemented some of the harshest discriminatory laws (''ghiyar'') against the Jews of Yemen, which culminated in the expulsion of all Jews (Exile of Mawza) to a hot and arid region in the Tihama coastal plain. The Qasimid state was the strongest Zaydi state to ever exist. See Yemeni Zaidi State for more information.