According to a recently-released United States government document, its Central Intelligence Agency (CIA) had advanced warning of a terrorist attack on a Cuban airliner that killed all 73 people aboard in 1976.

The document did not say what the CIA did after receiving the tip that June from anti-Castro militant Luis Posada Carriles, who had previously worked for the CIA, that fellow exiles were plotting to bring down a Cubana airliner. The Cubana plane, on a flight from Venezuela to Cuba, blew up shortly after taking off from a stopover in Barbados on October 6.

Several near misses followed his warning with a bomb aboard a Cubana Airlines plane leaving Panama failing to detonate and then a bomb in a suitcase exploded before being loaded on to a Cubana plane leaving Jamaica, according to a confidential U.S. State Department memo previously released by the National Security Archive.

Detained

Now aged 78, Posada currently resides in a Texan jail having been detained last year for entering the U.S. illegally.

In Kingston on the weekend, the Cuban Embassy organised a rally against past attacks on Cuba by exiles, dropping flowers into the harbour in remembrance of the victims and to call for Mr. Posado to be put on trial since they hold him responsible for the attack.

"It seems that he's going to get free and for us he's a terrorist and it's not only that, it's a lot of (his) actions," Cuban Ambassador Gisela Garcia Riveria told The Gleaner. "He's a very well known, recognised terrorist."

Mr. Posada trained with the CIA for the botched Bay of Pigs invasion in 1961 and served in the U.S. Army in the early 1960s.

Accused of involvement in the October 6 bombing he was still hired by the U.S. to deliver weapons to Nicaraguan Contra rebels in an illegal operation during the Ronald Regain Presidency in the 1980s. He also acknowledged, and then denied, a role in Havana hotel bombings in 1997 that killed a tourist.

In 2000, he was arrested for allegedly plotting to assassinate Cuban President Fidel Castro during a summit in Panama, before being pardoned in 2004.

Venezuelan President Hugo Chavez has accused the U.S. of protecting a terrorist as he seeks the extradition of Posada, a naturalised Venezuelan. A U.S. immigration judge has ruled against him being extradited to Cuba or Venezuela, citing fears that he would be tortured.

The CIA has always denied involvement in the attack.