The National Assembly grants "full power" to Premier Lon Nol, declares a state of emergency, and suspends four articles of the constitution, permitting arbitrary arrest and banning public assembly. Lon Nol and First Deputy Premier Prince Sisowath Sirik Matak had conducted a bloodless coup against Prince Norodom Sihanouk the day before and proclaimed the establishment of the Khmer Republic.
Between 1970 and 1975, Lon Nol and his army, the Forces Armees Nationale Khmer (FANK), with U.S. support and military aid, fought the communist Khmer Rouge for control of Cambodia. When the U.S. forces departed South Vietnam in 1973, both the Cambodians and South Vietnamese found themselves fighting the communists alone. Without U.S. support, Lon Nol's forces succumbed to the Khmer Rouge in April 1975. The victorious Khmer Rouge evacuated Phnom Penh and began reordering Cambodian society, which resulted in a killing spree and the notorious "killing fields." Eventually, hundreds of thousands of Cambodians were murdered or died from exhaustion, hunger, and disease. During the five years of bitter fighting, approximately 10 percent of Cambodia's 7 million people died.