Operation Sheridan Sabre  Operation Sheridan Sabre was a security operation during the Vietnam War in Bình Long Province to prevent People's Army of Vietnam (PAVN) infiltration from Cambodia, that took place from 7 November 1968 to 4 April 1969. On 26 October the 1st Cavalry Division was ordered to move from northern I Corps to III Corps northwest of Saigon near the Cambodian border in an operation named Operation Liberty Canyon. The 3rd Brigade, 1st Cavalry Division was the lead element of the Division and was air-lifted to Quần Lợi Base Camp to begin operations. The 1st Brigade, 1st Cavalry Division established a base of operations at Tây Ninh Combat Base, while 2nd Brigade, 1st Cavalry Division concluded Operation Comanche Falls III and began moving to its base of operations at Tonle Cham Camp. The operation was part of II Field Force, Vietnam's Operation Toan Thang II and began on 7 November 1968, as the 1st Cavalry Division moved into III Corps. The mission of the division during this operation was to conduct offensive operations in an assigned tactical area of operations, interdict movement of major PAVN forces south into critical areas of III Corps, locate and destroy PAVN forces, facilities, and material, and be prepared to deploy all or part of the division throughout III/IV Corps. The 1st Brigade was to conduct offensive operations against PAVN forces and installations in northeastern Tây Ninh Province with one battalion making a reconnaissance in force north and west of Thien Nhon (). The 2nd Brigade was located on Landing Zone Rita () and on Landing Zone Billy () and was to conduct offensive operations in the Fishhook area and Saigon River infiltration routes to destroy PAVN forces and installations and secure Highway 13 in the zone. The 3rd Brigade at Quần Lợi was to conduct offensive operations in the vicinity of Serges Road (a PAVN/Vietcong (VC) infiltration route also known as the Song Be corridor that followed the Binh Long and Phước Long Province boundary south southeast from Sông Bé Province) to interdict PAVN infiltration routes and to locate and destroy PAVN caches in that area. One battalion based vicinity Sông Bé Base Camp was to conduct reconnaissance-in-force operations in the vicinity of Adams Road (a PAVN/VC infiltration route through mountains east of Sông Bé Province).