(CBS News) It is one of America's greatest mysteries: What happened to three men after they pulled off a daring prison break at Alcatraz in 1962? Only the worst criminals were sent to Alcatraz. And for 29 years, it was the most secure federal prison in the country – surrounded by the cold, rough waters of the Pacific. But brothers John and Clarence Anglin and Frank Morris disappeared into the night and have never been found.
The men have become folklore – fueled by Hollywood and popular shows. And in the last 55 years, theories about their fate have multiplied as new evidence surfaces.
A letter allegedly written by one of the escapees recently came to light. CBS San Francisco exclusively obtained it from a source.
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