Korean War two years of fighting became a war of attrition, with the front line close to the 38th parallel. The war in the air, however, was never a stalemate. North Korea was subject to a massive bombing campaign. Jet fighters confronted each other in air-to-air combat for the first time in history, and Soviet pilots covertly flew in defense of their communist allies. The fighting ended on 27 July 1953, when an armistice was signed. The agreement created the Korean Demilitarized Zone to separate North and South Korea, and allowed the return of prisoners. However, no peace treaty was ever signed,
South Korea in the Vietnam War Lai Đại Hàn were ostracised and neglected by Vietnamese society following the war. Korean civil groups have discussed the issue considerably, and calls have been made for a Korean inquiry, in line with the Truth and Reconciliation Commission on massacres committed by government forces during the Korean War, known as the People's Tribunal on War Crimes by South Korean Troops during the Vietnam War. The alleged war crimes have had an impact upon South Korea–Vietnam relations and led the Vietnamese government to oppose the "commemoration of mercenaries" when South Korean President Moon Jae-in honoured the 50th Anniversary of South Korean