severely hampered Communist resupply in the region near the capital and in the Plain of Reeds. Completing the first phase of the Sealords program, in January 1969 PBRs, Assault Support Patrol Boats (ASPB), and other river craft established patrol sectors along canals westward from the Vam Co Tay to the Mekong River in Operation Barrier Reef. Thus, by early 1969 a patrolled waterway interdiction barrier extended almost uninterrupted from Tay Ninh Province northwest of Saigon to the Gulf of Siam. Further operations would be carried out on the Cua Dai and Hoi An Rivers in Quang Nam Province in I Corps, on the Saigon River as far north as Dau Tieng Base Camp in the Michelin Rubber Plantation in III Corps and on the Ca Mau Peninsula waterways in IV Corps. During the Cambodian Incursion in May 1970, Sealords task forces sailed up the Mekong River, crossing the Cambodian border, with forces reaching as far upriver as the capital of Phnom Penh. Since Operation Sealords was designated as a part of the U.S. military's Vietnamization program, in February 1969 the U.S. Navy began handing over nearly 250 patrol craft and 500 motorized junks, formerly part of Task Forces 116 and 117, to the RVNN. Virtually all of these watercraft were captured by the People's Army of Vietnam in 1975. The U.S. Navy's role in Sealords officially ceased in April 1971 and became the complete responsibility of the RVNN. See also Lists of allied military operations of the Vietnam War Operation Game Warden Operation Market Time Mobile Riverine Force Notes Citations References cited External links "By Sea, Air, and Land" Chapter 4 Sealords Sealords 1968 in Vietnam 1969 in Vietnam 1970 in Vietnam