Crime Crime History Inmates Who Escaped from Alcatraz 60 Years Ago Pictured in Just-Released Age-Progressed Images Frank Morris, Clarence Anglin and his brother John Anglin escaped from the notorious penitentiary with a raft made of raincoats and left behind plaster dummies in their beds By Christine Pelisek Christine Pelisek Christine Pelisek is a senior crime writer at PEOPLE. She has been working at PEOPLE since 2014. People Editorial Guidelines Published on June 21, 2022 03:19PM EDT 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. The three convicted bank robbers escaped from "The Rock" in June of 1962 by climbing through the prison's vent systems. They made their escape off the island in a 6-by-14-foot, homemade rubber raft that was made from raincoats. It's still unclear to this day if the three men survived the strong currents and frigid Bay waters around Alcatraz. According to the FBI, authorities found pieces of a woode n paddle and a rubber inner tube in the water around Alcatraz after the escape. They also found a homemade life-vest washed up on a nearby beach. Getty (3); U.S. Marshals (3) Supervising Deputy Mike Dyke of the U.S. Marshals Service told CBS News in 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 "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. U.S. Marshals 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. Authorities discovered the men spent 18 months planning their escape. They used spoons as well as a homemade drill made from the motor of a broken vacuum cleaner to widen the air vents in their cells and squeezed through to a utility corridor, the FBI said. The Denver Post via Getty 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. In 2013, a letter allegedly written by John Anglin was sent to the San Francisco Police Department, KPIX5 reported. The letter writer said, "We all made it that night but barely!" Want to keep up with the latest crime coverage? Sign up for PEOPLE's free True Crime newsletter for breaking crime news, ongoing trial coverage and details of intriguing unsolved cases. He said that his brother died in 2011 and Morris died in 2008. The letter writer also revealed he was suffering from cancer and said, "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. This is no joke." According to KPIX5, the U.S. Marshals Service sent the letter to the FBI for analysis and the results came back inconclusive.