SPRINGFIELD, VA (AP) - Nguyen Ngoc Loan, whose execution of a Viet Cong prisoner on the streets of Saigon in 1968 became one of the most chilling images of the Vietnam War, died Tuesday. -snip- On Feb. 1, 1968, Loan was director of South Vietnam's national police and the North Vietnamese had just begun the Tet Offensive, their huge military push southward. Firefights had broken out all over Saigon, and Loan's police were trying to rid the South Vietnamese capital of Viet Cong guerrillas. Loan led the prisoner, his hands bound, onto a street corner and in front of a...