The Khmer Serei and The Khmer Kampuchea Krom Militia
The Khmer Serei also had loose links with the US-backed Front de Lutte du Kampuchea Krom militia, or "White Scarves" (Khmer: Kangsaing Sar; Vietnamese: Can Sen So), of southern Vietnam. This group, originally founded by a Khmer Krom monk named Samouk Sen, sought Khmer Krom independence and regularly clashed with the Viet Cong: it expanded in the 1960s and later became affiliated to FULRO, a paramilitary organisation for Vietnamese minority groups. Members of both the Khmer Kampuchea Krom and the Khmer Serei were trained by the US military for clandestine operations during the Second Indochina War as part of MIKE Force, and were partly financed and armed by the Central Intelligence Agency. At their peak in 1968, the Khmer Serei and related forces were thought to number up to 8000 men.
After the 1970 Lon Nol coup, Son Ngoc Thanh became a government minister, and members of the Khmer Serei and Khmer Kampuchea Krom militias - some of whom had been infiltrated into the Cambodian army prior to the coup - appeared on the streets of Phnom Penh. However, due in part to the desperate military situation, and in part to Lon Nol's suspicion that this comparatively well-trained force might be used against him by his rivals, they were deliberately thrown into the most grueling battles and largely shattered.
Son Ngoc Thanh was dismissed from the government in 1972, and exiled himself in South Vietnam, where he was arrested following the Fall of Saigon; the remaining Khmer Serei in South Vietnam were eliminated by the North Vietnamese victory, while those in Cambodia itself were hunted down by the Khmer Rouge after the overthrow of Lon Nol's regime.
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