a Khmer Krom Buddhist monk, Samouk Sen, the group was nicknamed the "White Scarves" (; ) and allied itself with FULRO against South Vietnam. FULRO was an alliance of Khmer Krom, Montagnard, and Cham groups. The anti-Communist prime minister of the Khmer Republic (1970 - 1975) Lon Nol planned to recapture the Mekong Delta from South Vietnam. After the Fall of Saigon in 1975 and the Communist take-over of all of Vietnam, the Kampuchea Krom militia found itself embattled with People's Army of Vietnam. Many of the fighters fled to Khmer Rouge-controlled Democratic Kampuchea hoping to find a safe haven to launch their operations inside Vietnam. The "White Scarves" arrived in Kiri Vong District in 1976, making overture to the Khmer Rouge and appealing to the leader Khieu Samphan directly for assistance. The force was disarmed and welcomed initially. Subsequent orders from the Khmer Rouge leadership however had Samouk Sen arrested, taken to Phnom Penh, tortured, and killed. His force of 67 Khmer Krom fighters were all massacred. During the following months, some 2,000 "White Scarves" fighters crossing into Kampuchea were systematically killed by the Khmer Rouge. In the late 1970s, the Kampuchean Revolutionary Army attacked Vietnam in an attempt to reconquer the areas which were formerly part of the Khmer Empire, but this military adventure was a total disaster and precipitated the invasion of Democratic Kampuchea by the People's Army of Vietnam and subsequent downfall of the Khmer Rouge, with Vietnam occupying Kampuchea. Human rights Many independent NGOs report that the human rights of the Khmer Krom are being violated by the Vietnamese government. Khmer Krom are reportedly forced to adopt Vietnamese family names and speak the Vietnamese language. As well, the Vietnamese government has cracked down on non-violent demonstrations by the Khmer Krom. Unlike some other minority people groups in Vietnam, the Khmer Krom are largely unknown by the Western world, despite efforts by associations of exiled Khmer Krom such as the Khmers Kampuchea-Krom Federation to publicize their plight with the Unrepresented Nations and Peoples Organisation. No Western government has yet raised the matter of the Khmer Krom's human rights with the Vietnamese government. The "Human Rights Council Universal Periodic Review Working Group" was visited by the Khmer Kampuchea Krom Federation. Notable people Chau Sen Cocsal Chhum, Prime Minister of Cambodia (1962) Ieng Sary, Khmer Rouge member and Minister of Foreign Affairs of Democratic Kampuchea Son Ngoc Minh,