 Operating in Phước Tuy, Biên Hòa and Long Khánh Provinces, it was composed of both South Vietnamese VC guerrillas and North Vietnamese People's Army of Vietnam (PAVN) units.Given the task of isolating the eastern provinces from Saigon by interdicting the main roads and highways, including National Routes 1 and 15 and provincial routes 2 and 23, it proved a major challenge to Army of the Republic of Vietnam (ARVN) units that ventured into the province, demonstrating a capacity to mount regimental-size ambushes.The 274th Regiment was the stronger and better trained of the two.