Of the ten members of the CPK standing committee named in 1963, 6 were executed by Pol Pot after they took power in 1975 and before they were deposed in 1979.
In 1975, when the CPK seized power (although they never publicly announced that the CPK was in fact in power until 1977—instead publicly naming a fictitious group of United Front personalities who held nearly zero internal influence in formulating State policy but represented a broad sector of well known figures, including King Sihanouk, who retained the title of Head of State while under house arrest ), they held another Party Congress and named as their standing committee members, in order of rank, Pol Pot, Nuon Chea, Sao Phim, Ieng Sary, Son Sen, Ta Mok, Vorn Vet, and Nheum. Of those 8 members, 3 were executed during the Khmer Rouge reign in power—Sao Phim, Vorn Vet, and Nhuem. They also named 22 members to the central committee of the CPK. Of these, 18 were ordered executed by the time the Khmer Rouge were ousted from power in 1979. The existence of the Party was never publicly acknowledged until 1977.
Among the first to be purged was Hu Yuon, who as finance minister, objected to the abolishing of markets and the use of currency. He was believed to have been executed in the months after the 1975 liberation of Phnom Penh.