Havana, Cuba (CNN) -- A member of the "Cuban Five" spy group renounced his United States citizenship at the U.S. diplomatic mission in Havana on Monday, removing the final obstacle to his permanent return to the island. Rene Gonzalez, a Cuban intelligence officer, was a member of a network of agents in South Florida that the Cuban government said was gathering intelligence to prevent terrorist attacks against Cuba; U.S. federal prosecutors called them a dangerous spy cell. The men were convicted in 2001, and ever since they have been the focus of a campaign by Cuban officials to free them.
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'Cuban Five' renounces U.S. citizenship as condition of staying in Cuba
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U.S. judge issued renunciation option for Rene Gonzalez on Friday
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Convicted spy would be lesser U.S. security risk in Cuba, judge writes
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Four others still serving sentences in U.S. prisons
Four men flying from @placeholder to Cuba were shot down and killed by Cuban air force jets.