By then, Sar and Sary were both high-ranking members of the party. Their positions had been confirmed at a special party congress convened in the wake of the Siem Reap demonstrations, but before Sihanouk’s return. At the meeting, Sar replaced Tou Samouth as secretary of the party. Nuon Chea kept the second position, although it is likely that he had hoped to obtain the first; the third position was occupied by either Sao Phim or Ieng Sary. Recent research, based on Vietnamese Communist sources, suggests that Chea was kept out of the top position by rumors, spread by Saloth Sar, that he had recently received a sum of money from his cousin Sieu Heng. Nuon Chea himself, on the other hand, claimed in 1997 that “the Pracheachon group accused me of betrayal because I was a relative of Sieu Heng.” Chea went to discuss the issue with Saloth Sar, who “said to let him become secretary and I would be deputy secretary.” A 1974 party history noted that the congress had set new tasks and outlined new directions for the party, but this is doubtful, given the constraints of political struggle and the numerical weakness of the party. What was important about the congress was that it locked Saloth Sar, Nuon Chea, and Ieng Sary into positions in the party hierarchy that they retained for many years. Son Sen, who had studied with them in France, joined them on the Central Committee.42

Lon Nol’s list, therefore, named three party members on the Central Committee (Saloth Sar, Ieng Sary, Son Sen) and two members who were familiar with the organization’s inner workings (Chou Chet and Siet Chhae). Chou Chet had already left the city, and Siet Chhae was advised to desist from party business. Saloth Sar and Ieng Sary for their part decided to leave the capital and seek refuge in the eastern part of the country. According to Keng Vannsak, Sar had been eager to leave for some time and had accepted Vannsak’s advice to join former Khmer militants near Thboung Khmum in northern Kompong Cham. In fact, he probably concealed his true destination—a Vietnamese military camp known as “Office 100” on the Vietnamese-Cambodian border—from Vannsak, who was not privy to party secrets. Nuon Chea, who knew how to reach the base, transported Sar and other cadre there from Phnom Penh. Talking to Yugoslavian journalists in 1978, Pol Pot said: ”In 1963, I could not stay any more in Phnom Penh. I had to join the maquis. I was not very well known to the public. But Lon Nol’s police followed my activities. They knew me but they did not know exactly who I was. In Phnom Penh I was the general responsible [for] the movement in the capital; I was also in charge of liaison with the countryside.“43