Mr Barker said he had no regrets about the break-in
Former CIA agent Bernard Leon Barker, who took part in the Watergate burglary in Washington more than 30 years ago, has died in Miami at the age of 92.
In the course of a long and colourful career, Mr Barker was also one of the leaders of the failed CIA attempt to invade Cuba at the Bay of Pigs in 1961.
He had suffered from cancer and heart problems, the AP news agency said.
The Watergate break-in sparked one of America's biggest political scandals, toppling then-President Richard Nixon.
A quick run through the CV of the Cuban-born CIA operative is like taking a ride through some of the most controversial covert operations in late-20th century American history, says the BBC's Emilio San Pedro.
Not only was he was one of the leaders of the 1961 CIA attempts to invade Cuba, but his name was often discussed by American conspiracy theorists as having played a role in the assassination of John F Kennedy, allegedly in revenge for his failure fully to support the Bay of Pigs invasion.
But he was best known for being one of the five men who broke into the Democratic Party headquarters in 1972 at the Watergate building in Washington, DC, at the behest of then President Nixon.
The men were attempting to plant wiretaps to spy on the Democrat opponent of Mr Nixon - an event which eventually led to the once-popular president resigning in disgrace two years later.
In his later years, Mr Barker remained unapologetic about his involvement in the Watergate scandal, for which he only served a little over a year in prison.
As an anti-communist activist, he said he remained convinced that Mr Nixon was "one of the best presidents" the United States ever had.