There was a letter sent to the FBI in 2018 that was claimed to have been written by one of the Anglin brothers. It stated that all three inmates had indeed escaped and survived and that they had lived long lives but the last living of the three needed long term care and wanted to turn himself in so that he could receive that care. The FBI said they couldn't authenticate it though.
No proof of their survival from the info given on the Alcatraz tour! Which was excellant may i add....
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