 At the time of the attack the base was defended by Special Forces Detachment A-110, ARVN Special Forces, CIDG and Seabees.A small command element with A and D Companies, 1/4th Marines and several tanks from the 3rd Tank Battalion were providing security for engineers that were clearing a 200 meter wide fire zone around Leatherneck Square.The well-organized attack fell primarily on Company D's northern perimeter with fierce hand-to-hand combat.