Operation Fa Ngum  Operation Fa Ngum (1–27 April 1972) was a Laotian military offensive aimed at capturing the villages of Ban Ngik and Laongam as bases for incursions onto the Ho Chi Minh Trail. The Central Intelligence Agency backers of Royalist guerrillas planned to use a combination of air mobility and route march assaults to clear Route 23 through the two towns. Defensive forces to be defeated were the People's Army of Vietnam 9th and 39th Regiments. At various times and in differing combinations, the Royalists would commit two regiments of guerrillas, a makeshift regiment of the Royal Lao Army, three battalions of Neutralists, and a detachment of armored cars. Fighting a two-phase battle, the Royalists displaced the two PAVN regiments back towards the Vietnamese border. The Royalists both gained and gave up the open air cemetery of Ban Ngik. The PAVN returned westward toward the Thai border as the Royalists fell back. Enfeebled by mutiny and a serious casualty rate, the Royalists ended Operation Fa Ngum with a weak defensive blocking position at Laongam on Route 23. The Ho Chi Minh Trail was central to the People's Army of Vietnam (PAVN) strategy for the conquest of South Vietnam during the Second Indochina War. When a series of nine CIA-sponsored incursions from Military Region 3 (MR 3) and Military Region 4 (MR 4) of the southern panhandle of the Kingdom of Laos during 1969 and 1970 failed to interdict the Trail, the massive Operation Lam Son 719 was staged on 8 February 1971 to cut it. In the wake of this failure, Central Intelligence Agency (CIA) backed Laotian guerrillas and Royal Lao Government (RLG) military irregulars made further attempts at severing the Communist logistical lines of communication. Operation Sinsay in early 1972 had followed late 1971's Operation Thao La in attempts to control the strategic Bolovens Plateau that overlooked the Ho Chi Minh Trail; both had maintained tenuous holds on the Plateau. Operation Sinsay ended poorly; the troops that had achieved the momentary success of capturing their objective at Loangam on Route 23 had left the village three days later, at the end of March 1972. On 1 April 1972, the regimental-sized "Groupement Mobile 32" (GM 32) was helilifted over the opposing People's Army of Vietnam's 9th Regiment to land in its rear.