Cold War-Style Spy Swap Key To US-Cuba Deal

A prisoner exchange at the heart of a surprise restoration of diplomatic ties between the US and Cuba has led to the release of four top spies.

As cameras focused on American Alan Gross' arrival on US soil for the first time in five years on Wednesday, an unidentified Cuban man who served as a US intelligence agent was freed after two decades in captivity.

"This man, whose sacrifice has been known to only a few, provided America with the information that allowed us to arrest the network of Cuban agents that included the men transferred to Cuba today, as well as other spies in the United States," Barack Obama said.

The President called the spy "one of the most important intelligence agents that the United States has ever had in Cuba".

Mr Obama revealed the spy swap while announcing a major policy shift in US-Cuba relations .

While some in Congress criticised the President's decision, Cuba rejoiced over the long-sought release of three members of a spy group known as the Cuban Five.

The men, who are hailed as heroes in Cuba, operated in Florida in the 1990s.

They were convicted in 2001 in Miami on charges including conspiracy and failure to register as foreign agents in the US.

Two members were previously released after completing their sentences.

The "Five Heroes", as they are known in Cuba, are fixtures in state media and their faces grace billboards across the communist-ruled island.

Schoolchildren are taught their names and take part in public acts demanding their release.

The group is reviled, however, by many Cuban exiles living in South Florida.

One member, Gerardo Hernandez, was serving a life sentence on charges of murder conspiracy related to the Cuban air force's 1996 shoot-down of two planes.

The planes were flown by Brothers to the Rescue, an exile organisation that sought to aid migrants at sea.

Rene Gonzalez and Fernando Gonzalez, who are not related were released in October 2011 and February 2014, respectively.

The last three still in American prisons were Hernandez, Antonio Guerrero and Ramon Labanino.