The four men were members of a group known as Brothers to the Rescue that organized humanitarian missions over the Caribbean, seeking to find wayward Cuban refugees adrift at sea attempting to reach Florida. The Cuban military shot their planes down without any provocation and has never justified the murders, killing all four. Only one person — Gerardo Hernandez, a spy convicted of sharing pivotal information with the Castro regime that allowed it to target the victims — ever went to prison for the crime. 

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