In 1749, the Mughal ruler was induced to cede Sindh, the Punjab region and the important trans Indus River to Ahmad Shah Durrani, also known as Ahmad Shah Abdali, in order to save his capital from Afghan attack. Ahmad Shah next sent an army to subdue the areas north of the Hindu Kush mountains. In short order, the Ahmad Shah's powerful army brought under its control the Tajik, Hazara, Uzbeks, Turkmen, and other tribes of northern Afghanistan. Ahmad Shah invaded the remnants of the Mughal Empire a third time, and then a fourth, consolidating control over the Kashmir and Punjab regions, with Lahore being governed by Afghans. He sacked Delhi in 1757 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 India to return to Afghanistan.