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,
Thailand in the Korean War outpost hills along the front line while having a truce talk at Panmunjeom. A typical hill battle was waged at "Porkchop Hill", then held by soldiers of the 21st Thai Infantry Battalion, who repulsed an attack by the Chinese People's Volunteers. After this victory, the United States military awarded one Thai soldier the prestigious Legion of Merit, while 12 received Silver Stars and 26 were awarded a Bronze Star Medal. They were given the nickname "Little Tigers" by General James Van Fleet, commander of the 8th US Army. The Chinese made an all out effort to capture Porkchop Hill, attacking