Operation 34A

Operation 34A (full name, Operational Plan 34A, also known as OPLAN 34Alpha) was a highly classified U.S. program of covert actions against the Democratic Republic of Vietnam (DRV or North Vietnam), consisting of agent team insertions, aerial reconnaissance missions and naval sabotage operations. Though begun in 1961 by the Central Intelligence Agency, in 1964 the program was transferred to the Military Assistance Command, Vietnam Studies and Observations Group (SOG) during Operation Parasol/Switchback. The SOG was the cover name for a multi-service unconventional warfare task force under the direct guidance and control of the Pentagon.

After a series of operations, in which Republic of Vietnam (RVN or South Vietnam) commandos were captured after insertion into North Vietnam, SOG shifted the emphasis of its activities to maritime operations. A small fleet of fast patrol boats was acquired for use in the landing of small action teams and the offshore bombardment of small DRV military facilities (such as radar installations), with the pace of these operations doubling between June and July 1964, following the intense engagement at Chan La. The Norwegian intelligence officer Alf Martens Meyer, recruited three Norwegian sailors to participate in these raids. The Norwegians ran SWIFT boats from Da Nang, with South Vietnamese commandos on board. The three Norwegians told their story in a TV documentary for Norwegian Broadcasting Corporation in December 2000.

Starting in mid-1962, the U.S. Navy began conducting electronic surveillance operations conducted by a division of ocean-going minesweepers (MSO) operating along the coast of North and South Vietnam. The minesweepers were equipped with portable vans containing highly sophisticated electronic surveillance equipment. The minesweepers fueled on occasion at a South Vietnamese fueling station located near the fishing port (DaNang) and took on evidence from CIA operatives which allegedly tended to prove that China and Russia were supplying the Viet Cong with weapons and other material. Occasionally, usually between midnight and 3 am, DRVN gunboats would approach the minesweepers at high speed and then peel off and return to a DRVN naval base operating on an island north of the 30th parallel. The gunboats made threatening maneuvers but never actually attacked the minesweepers. The maneuvers were reported to CINC Pac Fleet and the Pentagon in nightly Top Secret cryptograph messages. The minesweepers were essentially defenseless should an attack occur. In early 1963, the minesweepers were relieved by a division of destroyers (the DESOTO patrols) who appear to have carried out the same electronic surveillance operations conducted by the minesweepers.

...
Wikipedia