THREE CIA-sponsored covert-action teams were loose in Cuba. It was the peak of the missile crisis when a false move on either side could have escalated into all-out war.

American attempts to overthrow Castro did not end with the failure of the April 1961 invasion of Cuba at the Bay of Pigs. On Nov. 30, 1961, President John F. Kennedy approved a covert action plan for sabotage and subversion against Cuba, code-named "Operation Mongoose." A Special Group (Augmented), the SG (A), and a headquarters under Maj. Gen. Edward Lansdale, provided direction from Washington, while the CIA's "Task Force W" in Miami, headed by William K. Harvey, another veteran covert-action officer, ran the operation.

During most of 1962, Task Force W built up its assets to include about 400 Americans, 2,000 Cubans, a private navy of fast boats, and an annual budget of about$50 million. Its early actions included contaminating a sugar export shipment from Cuba and arranging for the export of defective ballbearings from Europe to Cuba. By September it began raids into Cuba, and on Sept. 27 a CIA sabotage team was arrested in Cuba.

Other Cuban contra groups, not controlled by the CIA were also active. In August, one such group, Alpha 66, launched a daring speedboat strafing attack on a Cuban seaside resort hotel killing a score of Russians and Cubans. On Sept. 10 the same group shelled one British and two Cuban merchant ships just north of Cuba. Again on Oct. 7 they carried out a raid on the island.

While these raids were not controlled by American authorities, they were mounted from U.S. territory. Moreover, on Oct. 12 a State Department spokesman said that although the U. S. government did not "sanction" such attacks, it was not prepared to act against the emigres who undertook them, andwarned that foreign shippers who traded with Cuba took a risk.

On Oct. 4, Attorney General Robert Kennedy and CIA Director John A. McCone had an argument in the SG(A) over why the program was going so slowly inside Cuba. A decision was made to step up operations including the dispatch of more sabotage teams. Several meetings followed, including one on Oct. 16 sandwiched in between the first two White House meetings of what was to become President Kennedy's Cuban missile-crisis management team. High-level attention then shifted sharply to the missile crisis.

Covert actions were not totally forgotten, however. The State Department coordinator of Cuban affairs, Bob Hurwitch, even proposed sending Cuban emigre pilots in unmarked aircraft to bomb the missile sites, with a cover story that they were targeting oil refineries. But the idea evoked memories of the ill-fated Bay of Pigs air operation and Secretary of State Dean Rusk turned it down flat.

Mongoose did not rear its head again until after the exchange of letters by Chairman Nikita S. Khrushchev and President Kennedy on Oct. 28 outlined a settlement based on Soviet withdrawal of its missiles and an American pledge not to invade Cuba. One CIA operator in Task Force W became uneasy as a new sabotage group was about to be sent into Cuba and checked with Robert Kennedy. Everyone in the Washington SG(A) had forgotten about Mongoose and their own earlier instructions to step things up. On Oct. 30 Mongoose was suspended, and Lansdale was personally dispatched to Miami to close it down. By then Bill Harvey had prepared 10 six-man sabotage teams in Miami, and three had already been sent into Cuba.

By Nov. 8 crisis negotiations between U. S. and Soviet representatives in New York had become difficult. The United States had stiffened its insistence that light bombers being provided to Cuba by the Soviets were also "offensive weapons" and must go. Castro was blocking inspection of the removal of the missiles, as well as procedures to verify that offensive arms were not reintroduced. Under those circumstances, the United States maintained the naval quarantine of the island, and refused to give assurances against invading Cuba.

On that date, Nov. 8, one of the CIA-dispatched sabotage teams successfully blew up a Cuban factory. To the Soviets and Cubans, this act was probably seen as a subtle American reminder of its ability to harass the Castro regime. While that impression might even have helped American purposes at the time, the action was not a deliberate or controlled act and could have had very adverse consequences if, for example, it had occurred a few weeks later after an agreement had been reached.

Negotiations interrupted by the missile crisis resumed and led in late December to the "ransom" release of the 1,113 Bay of Pigs prisoners. Against the advice of both Dean Rusk and McGeorge Bundy, President Kennedy personally welcomed the Bay of Pigs veterans. In his speech, Kennedy extemporaneously interjected a promise to see their brigade flag fly in "a free Havana." The brigade veterans then went on to other things, some into the U.S. military and CIA (including some sent into the Congo in 1964), others breaking into Watergate in 1972, and others mining ports in Nicaragua in 1984.

In early 1963, the SG(A), Mongoose, and Task Force W were abolished. But covert operations were resumed only a few months later, and a new attempt made to assassinate Castro. That latter effort led to a tragic, ironic coincidence. On Nov. 22, 1963, the CIA's Desmond FitzGerald, who had replaced Harvey, in a meeting in Paris supplied American agent and former Castro comrade-in-arms Rolando Cubeles with a poisoned pen to give Castro. On the same day, President Kennedy was assassinated.

Covert operations were not a significant factor in the Cuban missile crisis, but they were involved -- and in ways not intended or desired. Twenty-five years after the missile crisis this little known episode reminds us that covert operations, and support for emigre Contras, can have unexpected effects under unusual circumstances. And despite efforts on all sides to avoid crises, they can arise.

Raymond Garthoff was a State Department official at the time of the Cuban missile crisis. He is the author of "Reflections on the Cuban Missile Crisis," published this week by The Brookings Institution.