In 1950, American advisors arrived in South Vietnam to prevent a takeover by communist North Vietnam, which was backed by China and Russia. After an attack on U.S. destroyers by North Vietnam gunboats in 1964, Congress approved a resolution allowing U.S. combat involvement. Soldiers had to learn new tactics as they faced dense jungles, malaria, heat, monsoon rain, enemy tunnels, and booby traps. They fought the North Vietnamese Army and the local Viet Cong in a jungle guerrilla war with no front lines, as the Viet Cong blended in with villagers. By the late 1960s, public support for the war had eroded. More than 58,000 were killed and 150,000 wounded, and the war's 120 billion dollar economic cost made continuation unsustainable. In January 1973, the signing of the Paris Peace Accords began the withdrawal of U.S. personnel. Without U.S. military support, communist North Vietnamese forces captured Saigon, the South Vietnamese capital, on April 30, 1975, ending the war. Jackson County lost 19 people killed and unknown hundreds wounded in the conflict.