Wednesday, June 27, 2007; A06

It was certainly a marriage of convenience. After Fidel Castro led a revolution that toppled a friendly government in 1959, the CIA was desperate to eliminate him. So the agency sought out a partner equally worried about Castro -- the Mafia, which had lucrative investments in Cuban casinos.

The plot, described in detail in CIA documents released yesterday, involved six poison pills, a bungled wiretapping and CIA operatives working with two mob bosses on the FBI's Ten Most Wanted list.

The CIA's efforts to assassinate Castro were documented by the Church Committee in 1975, based on the testimony of the key players, but the documents show that the agency's actions in the early 1960s still have the capacity to shock.

The CIA plan was known to only a few top officials, including then-CIA Director Allen Dulles. Robert A. Maheu, a former FBI agent, was asked by senior officials to contact Johnny Roselli, a high-ranking mobster he knew.

Maheu made the pitch on Sept. 14, 1960, at a hotel in New York City. He brought along James O'Connell, whom he identified as an employee but who was in reality chief of the CIA's operational support division. They offered to pay $150,000, but Roselli declined any pay.

Roselli later introduced Maheu at the Fontainebleau Hotel in Miami Beach to "Sam Gold" and "Joe," who had connections in Havana. Flipping through Parade magazine, Maheu later discovered to his shock that "Sam" and "Joe" were actually Momo Salvatore Giancana, the successor to Al Capone as head of the Chicago mob, and Santo Trafficante Jr., the head of the mob's Cuban operations.

Maheu told the CIA's security office, but the plan went forward, according to a summary written by the office's director, Howard J. Osborn. Giancana suggested slipping something into Castro's drink or food, and the CIA provided "six pills of high lethal content," according to the summary. But an initial assassin got cold feet, and the project was canceled before a second man could act.

The project was nearly exposed when Maheu was arrested for arranging the wiretapping of the room of comedian Dan Rowan, who Giancana suspected was having an affair with the mobster's girlfriend. When the wiretap technician was captured, he implicated Maheu, requiring the CIA to ask then-Attorney General Robert F. Kennedy to drop the prosecution.

Roselli later told columnist Jack Anderson about the plot after the CIA refused to help him fight deportation. He disappeared shortly after testifying to the Church Committee. His body was later found in a 55-gallon oil drum near the coastline of North Miami Beach.

-- Glenn Kessler