The Royalists destroyed five tons of Communist war materiel along the way. On 12 August, the Royalist regiment took Moung Wapi. On 15 August, it was relieved by allies of the Royalists, "Bataillon Infanterie 18" (BI 18) from Forces Armées Neutralistes. In July, this task force attacked eastward along Route 23. The PAVN 9th Regiment held firm at Laongam. The Royalists established a new fire base with four artillery pieces halfway between Laongam and the 13/23 intersection. An additional Thai battalion reinforced the Royalist assault force. A renewed attack captured Laongam on 5 September, but could push no further. On 25 September, in mid-battle, three of the Thai battalions in Laongam were designated as constituting a new regiment, "Groupement Mobile 401" (GM 401). One Thai battalion secured the new intermediate fire base. A sixth Thai battalion having joined the operation, there were two battalions free to attempt to move eastward along Route 23 into Communist territory. On 14 October, four PAVN PT-76 tanks supported infantry attacking the Thais. Two of the PT-76s were destroyed on 15 October, and the Vietnamese withdrew. On the 18th, the PAVN struck again. By 0100 hours on the 19th, all the Thai infantry was in full flight, as GM 401 abandoned its headquarters staff and the new fire support base. The Communists overran the fire base, destroying three of four Royalist howitzers. An AC-130 Spectre gunship fire mission forced a Communist withdrawal and saved the 18 man headquarters. Two of the Thai battalions that had fled returned to establish a feeble defensive line while the Royalists planned another offensive.