peaceful withdrawal of the Vietnamese from Cambodian territory were rejected. As a consequence, Lon Nol called for UN intervention and international assistance. From 29 April and 1 May 1970, South Vietnamese and United States ground forces entered eastern Cambodia and captured vast quantities of enemy matériel, destroyed NVA and Viet Cong infrastructure and depots. Retreating Vietnamese troops pushed further west into Cambodia, destroyed FANK troops and positions, seriously destabilizing the Lon Nol government. After South Vietnamese and United States army withdrawal all of north-eastern Cambodia was controlled by the Vietnamese, who extensively supported, equipped local communist Khmer Rouge insurgents that had replaced FANK in these territories. A comprehensive assessment of the Khmer Republic's armed forces revealed serious shortcomings, such as the "lack of combat experience, equipment deficiencies,...lack of mobility" and "incompetent and corrupt officers". Although martial law was declared and total mobilization introduced, reliable and transparent administration, replacement of incompetent and corrupt officers, important personnel and educational reforms based on a modern military doctrine did not take place. FANK strategy focused on securing the central territory. The majority of the population occupied these rich, rice-growing areas as Vietnamese and Khmer Rouge control constituted the forested and mountainous lands north and east of the "Lon Nol Line." Two military offensives (Chenla I, in August 1970, and Chenla II, in August 1971) were undertaken in order to regain control of the fertile agricultural area of Kompong Thom north of Phnom Penh. Some initial success was not exploited and FANK was eventually defeated by the opposing North Vietnamese Ninth Division and increasingly numerous and effective Khmer Rouge divisions. These troops had acquired considerable political momentum since the dethroned Sihanouk served as their new figurehead proclaiming war of national liberation. In 1970 Sihanouk announced the establishment of the Royal Government of National Union of Kampuchea (Gouvernement royal d'union nationale du Kampuchéa – GRUNK), which he claimed was legitimized by the National United Front of Kampuchea (Front uni national du Kampuchéa – FUNK). This rhetoric was particularly popular among the rural population and ethnic minorities. The RAK (Revolutionary Army of Kampuchea) was renamed the Cambodian People's National Liberation Armed Forces (CPNLAF). By 1972 FANK actions were mainly defensive operations for steadily shrinking government territory which by November 1972 had reached a point that required a new strategic realignment of the Lon Nol line. Lost were the rich rice-growing areas around the Tonlé Sap lake. The