A source told the Miami Herald on condition of anonymity that Gerardo Hernandez -- currently in a federal prison on spying charges -- may have information linking Raul Castro to the 1996 downings of Brothers to the Rescue civilian planes in international waters.
Ten years ago, Cuban MiGs shot down two unarmed civilian airplanes killing three U.S. citizens.
Hernandez faces life in prison on spying charges if his appeal fails.
His lawyer Paul McKenna, however, said that his client has no such information and characterized assertions that he might as "ridiculous."
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