Alcatraz mystery deepens after discovery of letter signed by fugitive claiming prisoners survived escape

Authorities have never determined whether brothers John and Clarence Anglin and fellow inmate Frank Morris survived the daring jail break. The FBI closed its case in 1979, concluding the men were unlikely to have survived the 1.5-mile journey across San Francisco Bay’s frigid waters from the island prison to the mainland. “My name is John Anglin,” the handwritten missive begins.