About mid-March, the 26th Marines S-2 began noting an exodus of major NVA units from the Khe Sanh TAOR. Most of these reports came from mountain tribesmen who provided valuable information on enemy troop dispositions throughout the siege. The =325C NVA Division Headquarters= was one of the first to pull out toward Laos, followed by elements of the =95C= and =101D Regiments= which also relocated to the west. About the same time, the =304th NVA Division= withdrew several thousand meters to the southwest. The enemy still retained enough troops around the base to maintain pressure and thus the shelling and probes continued.(192) Closely correlated with the enemy's retrograde movement was another large influx of refugees into the KSCB. Most were Montagnards who had inhabited the smaller villages surrounding the base and unfortunately had become the pawns of war. When the fighting first broke out, the Allies advised them to evacuate their homes and move overland to Cam Lo or else they would be exposed to fire from both sides. During the period 23-28 January, 1,050 Vietnamese and tribesmen with their families were air evacuated to Da Nang and then on to Quang Tri City. About the same time, some 1,800 tribesmen completed an overland trek from Khe Sanh to Cam Lo by way of the the Ba Long Valley. Later an additional 3,000 or more attempted to reach Cam Lo, but during the journey, the North Vietnamese intercepted this group and directed them back into the Khe Sanh area. Presumably, the NVA used the Montagnards to screen troop movements and confuse American intelligence. The next surge of refugees into the combat base occurred in early February following the attack on Lang Vei. On 7 March, the tribesmen again started to filter into the base. They were screened, interrogated, and processed for evacuation in the FOB-3 compound. As many as 661 were airlifted to eastern Quang Tri Province in a single day and the total for March was 1,432.(193) Although the enemy had scaled down his forces, the heavy incoming continued to plague the Marines. On the average, the base received about 150 rounds a day during March. During the course of a normal day, the preponderance of fire was from the 82mm mortars but on peak days the greatest number of rounds was from the heavier artillery. On 23 March, the KSCB received its heaviest daily saturation of the month--1,109 rounds. Of these, over 30 percent were from the enemy's big guns in Laos. In addition to the indirect fire, the Marines took a sprinkling of recoilless rifle shells; but these weapons were easy to spot because of their large back blast and thus were vulnerable to air attack and counterbattery fire.(194)