密接支援
On 20 June, Company C, 2nd Battalion (Airborne), 503rd Infantry (C/2-503) discovered the bodies of a Special Forces CIDG unit that had been missing for four days on Hill 1338, the dominant hill mass south of Dak To. Supported by A/2-503, the Americans moved up the hill and set up for the night. At 06:58 the following morning, Alpha Company began moving alone up a ridge finger and triggered an ambush by the 6th Battalion of the 24th PAVN Regiment. Charlie Company was ordered to support, but heavy vegetation and difficult terrain made movement extremely difficult. Artillery support was rendered ineffective by the limited range of visibility. Close air support was impossible for the same reasons. Alpha Company managed to survive repeated attacks throughout the day and night, but the cost was heavy. Of the 137 men that comprised the unit, 76 had been killed and another 23 wounded. A search of the battlefield revealed only 15 dead North Vietnamese.