Ahmad Shah began his campaign by capturing Ghazni from the Ghilji Pashtuns, and wresting Kabul and Peshawar from Mughal-appointed governor Nasir Khan, conquering the area up to the Indus River in 1947. In 1749, the Mughal ruler was induced to cede Sindh, the Punjab region and the important trans Indus River to Ahmad Shah in order to save his capital from Afghan attack. Having thus gained substantial territories to the east without a fight, Ahmad Shah turned westward to take possession of Herat, which was ruled by Nader Shah's grandson, Shah Rukh of Persia. Herat fell to Ahmad after almost a year of siege and bloody conflict, as did Mashad (in present-day Iran). Ahmad Shah next sent an army to subdue the areas north of the Hindu Kush mountains. In short order, the powerful army brought under its control the Turkmen, Uzbek, Tajik and Hazara tribes of northern Afghanistan. Ahmad Shah invaded the remnants of the Mughal Empire a third time, and then a fourth, consolidating control over the Punjab and Kashmir regions. Then, early in 1757, he sacked Delhi, but permitted the Mughal dynasty to remain in nominal control of the city as long as the ruler acknowledged Ahmad Shah's suzerainty over Punjab, Sindh, and Kashmir. Leaving his second son Timur Shah to safeguard his interests, Ahmad Shah left Hindustan (India) to return to Afghanistan.