In late December 1951, Trinquier was again in Indochina for his third tour – this time in the newly formed Groupement de Commandos Mixtes Aéroportés (GCMA) (Composite Airborne Commando Group) commanded by Edmond Grall. Trinquier took over the command of the GCMA in early 1953 and directed the fighting behind Viet Minh lines, creating a maquis in the Tonkinese upper region and in Laos, totaling around 30,000 men. Trinquier's maquis contributed to the successful evacuation of the fortified airhead at Na San, in August 1953, and the reoccupation of the Phong Saly and Sam Neua provinces. After the French withdrawal following the defeat of Dien Bien Phu, Trinquier's maquis was left behind and hunted down by Ho Chi Minh's forces.