In 1962, three inmates escaped from the notorious Alcatraz Island penitentiary and were never seen again.

Last week, the U.S. Marshals Service released new age-progressed images of the inmates: Frank Morris, Clarence Anglin and his brother, John Anglin, who would all be in their 90s today.

It’s still unclear to this day if the three men survived the strong currents and frigid Bay waters around Alcatraz.

Getty (3); U.S. Marshals (3)

Frank Lee Morris, Clarence Anglin, John William Anglin

Supervising Deputy Mike Dyke of the U.S. Marshals Service toldCBS Newsin 2011 that he believed the three men may have survived the journey. “I think probably the brothers lived … but there’s a chance that all three of them could have lived and they just split up once they left. There’s no body recovered. I can’t close the case.”

U.S. Marshals

The image, taken in Clarence Anglin’s cell, shows how the dummy heads were arranged to fool the guards into thinking the inmates were still asleep.

“There’s still a chance,” he added. “You can’t rule out the fact that they died. But you can’t rule out the fact that they lived.”

According to the FBI, Morris, a bank robber and burglar, was sent to Alcatraz — where famous inmates including Al Capone, George “Machine Gun” Kelly and the Birdman of Alcatraz served time — in 1960. John Anglin and his brother Clarence arrived soon after.

All three men knew each other from previous prison stays.

On the morning of June 12, 1962, guards discovered the three inmates missing from their beds. In their place were dummy heads made of plaster, flesh-tone paint and real human hair, the FBI said.

The Denver Post via Getty

JUN 14 1962, DEC 5 1993; Where Alcatraz Prison Break Started; A prison guard kneels by hole in Frank Morris' cell through which he and John and Clarence Anglin escaped. Prison officials report hole was dug with broken spoons.

From there, the men clambered up a series of pipes to the prison roof and then slid down a smokestack to the prison grounds where they jumped a fence, made their way to the northeast shore of the island and set off to the mainland, according to the FBI.

The letter writer said, “We all made it that night but barely!”

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He said that his brother died in 2011 and Morris died in 2008.

According to KPIX5, the U.S. Marshals Service sent the letter to the FBI for analysis and the results came back inconclusive.

source: people.com