Shortly after the March 1970 coup, however, the French military mission suspended all the cooperation with the Cambodian armed forces, thus depriving the new MNK of vital training and technical assistance.
Upon several attacks against merchant vessels anchored at Chrui Chhangwar Naval Base in early 1972, the MNK Fleet Command created a regimental-sized Harbour Defense Unit, the "Choc Commandos" () comprising two rifle battalions, to patrol its major port facilities and provide VIP protection.