A letter being made public by a San Francisco television station suggests that one of the most infamous prison escapes in history might have been a success. KPIX in San Francisco says the SFPD received a letter in 2013 from someone purporting to be John Anglin, a bank robber and one of three inmates who escaped from the island prison Alcatraz in 1962. They were never found and authorities have said the men likely died in the unforgiving waters of the bay after their elaborate escape attempt. In the letter, the writer asserts his identity and says the escape worked -- but just barely. He says he's 83 years old and is in bad shape from cancer. He offers to give his exact location in exchange for no more than one year in jail and access to medical care. The escape was the basis for the 1979 movie, “Escape From Alcatraz” starring Clint Eastwood as Frank Morris. The letter says his fellow escapees, his brother Clarence and Morris, died in recent years. The FBI has reportedly reopened the case and examined the letter. They looked for DNA, fingerprints and analyzed the handwriting, all with inconclusive results.