 From February–March 1967 the Marines launched Operation Prairie II a series of sweeps from Cam Lộ to Con Thien resulting in 93 Marines and 694 PAVN killed.In March 1967 Route 9 west of Cam Lộ was reopened to Khe Sanh for the first time since 1964.The road would suffer numerous ambushes making it dangerous if not altogether unusable.