On October 22, 1953, the French battalion embarked on the and headed for Indochina, where it was expanded into a two battalion regiment and formed the nucleus of the French "Groupement mobile 100." During their service in Indochina, the unit (under its new title of "Le Regiment de Corée") participated in the brutal Battle of Mang Yang Pass along "Route coloniale 19" in June and July 1954, where it suffered heavy casualties. Between its arrival in Indochina and the cease-fire on July 20, 1954, the 1st Battalion suffered 238 killed or wounded, and the 2nd Battalion 202 killed or wounded. In addition, 34 Indochinese assigned to the battalion were killed in action. On September 1, 1954, the "Regiment de Corée" was disbanded and reduced to battalion size. The battalion remained in Indochina until July 17, 1955, when it embarked from Saigon to Algeria to participate in the suppression of the ongoing insurrection.