Note: This is part six of a series. You can read part one, part two, part three, part four, and part five here.

Trimble was glad his team members returned to their perch atop Marble Mountain, because the NVA/VC forces attacked their position twice during daylight hours on August 23rd. “We were in contact with the enemy on and off during the course of the day,” Trimble told SOFREP. Aside from the attacks on their position, ST Rattler engaged enemy soldiers whenever they appeared on the mountain. “Several times we saw men with weapons…and we engaged them.” Whenever a sniper would open fire on FOB 4 below, team members would try to locate the enemy.

Down at FOB 4, more pieces fell into place. A couple of facts were obvious: The NVA had planned the attack for months, and they’d had good intelligence inside the camp to assist in picking the date. A Vietnamese woman who worked in the personnel administrative office had failed to report to work two days prior to the attack. It was later determined she was a communist agent, a sympathizer who had provided critical intelligence to the NVA regarding the layout and troop strength of FOB 4. Fortunately, in the two days following her departure, staff personnel had closed the old tactical operations center and the new TOC had been made fully operational on August 22nd.

The camp security force had been infiltrated by the NVA. Up until two weeks before the attack, the fearless Nungs had been assigned to base security for several months. The Nungs were a totally trustworthy fighting force trained by Special Forces. For some reason, the Nungs were replaced by members of the South Vietnamese QC (Quan Canh, military police), a corrupt organization known more for its political connections than its fighting prowess. It was well known they could not be removed without the explicit blessings of both local South Vietnamese politicians and the Saigon bureaucracy.

On the night of the attack, the indigenous mess hall had been secured by the NVA and a map of FOB 4 had been drawn on the wall, designating the main objectives of the attack. While the NVA sapper leadership was briefing its troops in the mess hall, two South Vietnamese indigenous soldiers stationed at FOB 4 had observed the suspicious activity and moved closer to investigate. Their bodies were among the dead collected the next morning, their throats cut before they could sound the alarm.

SOFREP has also learned the following facts that have never been reported publicly, nor were they known to many of the men who fought against the enemy sappers that night:

  1. An S-2 officer told the base commander and his command staff that he had heard several reports from other intelligence sources in Da Nang that an NVA Battalion, R-4, was slated to carry out the attack. The S-2 officer said they knew the NVA unit’s location, personnel strength, and past successes and failures. This is in addition to the three CIA flash messages received at FOB 4 warning of an imminent attack—warnings that base command staff ignored.
  2. On Aug. 22, 1968, less than 24 hours before the sapper attack, three platoons from FOB 4’s Hatchet Force command were sent by helicopter to a target 15-20 minutes southwest of the base. Their objective was to make and maintain contact with enemy forces from the 34th NVA Regiment, according to one of the platoon leaders of that mission, Lt. Geoff Fullen. If contact with the enemy could be sustained, local U.S. Marine units were scheduled to follow-up the engagement.

The 34th NVA Regiment was well-seasoned, well-equipped, and had between 700–900 men with artillery, rockets, and heavy mortars, in addition to a sapper company and a flamethrower company, Fullen said. After the detailed briefing, Fullen asked S-2 Officer Warren Williams how good the intelligence reports were, in his opinion. Fullen told SOFREP that Williams looked him in the face and then at the ground and said, “‘Maybe you better say a prayer.’ Those are the kind of things you never forget.”

The early morning launch ended with the helicopters taking heavy enemy fire from the primary, secondary, and alternate LZs, Fullen said. “We were on target maybe eight minutes, but it seemed more like eight days.” By 0730 hours, the Hatchet Force men had returned to FOB 4 where “the rest of the day was spent with head shaking and nervous laughter. We confirmed it was hot out there.”