Mysterious letter sent to police station was allegedly written by 1962 Alcatraz escapee

A mysterious letter sent to the San Francisco Police Department in 2013 by a man who claimed to have escaped from Alcatraz Federal Penitentiary was just obtained by local television station KPIX.

Prisoners John and Clarence Anglin and Frank Morris became the stuff of legends after escaping from the maximum-security California jail in 1962.

The trio of bank robbers made their notorious prison break by climbing down vents in the back of their cells before launching a makeshift raft — crafted out of inflated raincoats — into the San Francisco Bay. They then rowed away using homemade wooden paddles.

The next morning, guards found dummy heads crafted out of plaster, paper mache, paint and real human hair tucked into their beds.

The prison mug shots of convicts Frank Lee Morris, Clarence Anglin and John Anglin (L-R) in both their younger and older years are seen in this combination image made of handout photos from the U.S. Department of Justice. (Reuters)

Although many assumed that the trio drowned during their escape, some of their relatives have claimed that men survived and have secretly been in contact with their families throughout the years.

However, the escaped prisoners weren't heard from again by police until 2013, when a letter allegedly written by John Anglin was sent to police officers in San Francisco, claiming that he was still alive and in need of medical treatment.

"My name is John Anglin. I escape (sic) from Alcatraz in June 1962 with my brother Clarence and Frank Morris," the letter reads. "I’m 83 years old and in bad shape. I have cancer. Yes we all made it that night but barely!"

In his letter, the alleged Anglin reveals that Morris died in 2008 and Clarence in 2011. He then attempts to make a deal with police in order to receive the medical attention he says he desperately needs.

"If you announce on TV that I will be promised to first go to jail for no more than a year and get medical attention, I will write back to let you know exactly where I am," it adds. "This is no joke."

Although the FBI examined the letter for fingerprints and DNA and compared the handwriting to a former prison letter written by Anglin, all test results came back inconclusive.

Still, even if the letter was written by Anglin, it doesn't necessarily mean that law enforcement officials would be willing to cut him any sort of deal in exchange for medical treatment.

"There is absolutely no reason to believe that any of them would have changed their lifestyle and became completely law-abiding citizens after this escape," the U.S. Marshals Service write said in a statement to KPIX.

"The Federal Bureau of Prisons says that they drowned once they got off of Alcatraz and their bodies were swept out to the Pacific Ocean — end of story."

On March 21, 1963, Alcatraz closed its doors as a prison after 29 years of operation. It eventually reopened to the public as a tourist attraction in October 1973.

Over the nearly three decades (1934-1963) that the federal prison operated, 36 men, including two who tried to escape twice, were involved in 14 separate escape attempts, according to the Federal Bureau of Prisons. Of these, 23 were caught, 6 were shot and killed during their escapes and 2 drowned.

According to official records, no one has ever succeeded in escaping from Alcatraz — although, to this day, there are five prisoners listed as "missing and presumed drowned," Anglin included.

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