the People's Republic of China invaded Tibet, after taking over the rest of China from the Republic of China during the five years of civil war. In 1951, the Seventeen Point Agreement for the Peaceful Liberation of Tibet, a treaty signed by representatives of the Dalai Lama and the Panchen Lama, provided for rule by a joint administration under representatives of the central government and the Tibetan government. The Chinese have claimed that most of the population of Tibet at that time were serfs, bound to land owned by lamas. This claim has been challenged by other researchers (see serfdom in Tibet controversy). Any attempt at land reform or the redistribution of wealth would have proved unpopular with the established landowners. The Seventeen Point Agreement was put into effect only in Tibet proper; ergo, eastern Kham and Amdo, being outside the administration of the government of Tibet, were treated like territory belonging to any other Chinese province, with land reform implemented in full. As a result, a rebellion broke out in these regions in June 1956. The rebellion eventually spread to Lhasa, but was crushed by 1959. The 14th Dalai Lama and other government principals fled to exile in India. Beginning in the 1950s the Central Intelligence Agency trained Tibetans as paramilitaries. CIA and MI6 activities in Tibet (1950–1970) Agents of Western governments had infiltrated Tibet by the mid-1950s, a few years after Tibet had been annexed by the People's Republic of China. British MI6 agent Sydney Wignall, in his autobiography, reveals that he and John Harrop travelled to Tibet together in 1955 posing as mountaineers. Captured by the Chinese authority, Wignall recalled that he was surprised to find two CIA agents were already under Chinese detention. Clandestine military involvement by the U.S. began following the series of uprisings in the eastern Tibetan region of Kham in 1956. Several small groups of Khampa fighters were trained by the CIA camp and then airdropped back into Tibet with supplies. In 1958, with the rebellion in Kham ongoing, two of these fighters, Athar and Lhotse, attempted to meet with the Dalai Lama to determine whether he would cooperate with their activities. However, their request for an audience was refused by the Lord Chamberlain, Phala Thubten Wonden, who believed such a meeting would be impolitic. According to Tsering Shakya, "Phala never told the Dalai Lama or the Kashag of the arrival of Athar