Although the Viet Cong were operating in the daytime , they were able to hold their own against both the ARVN and the American aircraft .
The Army of the Republic of Vietnam ( ARVN ) , augmented by U.S. air support , responded to the invasion in force .
Although the Viet Cong were operating in the daytime , they were able to hold their own against both the ARVN and the U.S. aircraft .
The Army of the Republic of Vietnam ( ARVN ) , augmented by U.S. air support , responded to the invasion in force .