A convicted bank robber who spent a decade behind bars is heading back to prison after getting out and robbing three more banks, authorities said.

Frank Douglas, 61, of South Carolina, was sentenced to 20 years in prison Monday after pleading guilty to robberies in Athens, Conyers and North Augusta, S.C., federal prosecutors said in a news release.

The crime spree occurred in late 2017, just weeks after Douglas was released from prison after serving 10 years for five bank robberies. He was still on supervised release at the time.

Authorities said the spree started Nov. 20 when Douglas robbed a BB&T in Conyers. One week later, he held up a South State Bank in North Augusta, prosecutors said.

On Dec. 5, Douglas walked into an Athens Bank of America branch and passed the teller a note that read, “ALL LARGE BILLS I HAVE A GUN I WILL SHOOT,” authorities said. Nobody reported seeing a weapon but Douglas repeatedly told the teller he had a gun and that he would shoot her. He escaped with more than $6,700.

Douglas was arrested on an unrelated charge one week later, but investigators quickly linked him to all three hold-ups.

“Ten years in federal prison was apparently not a teaching moment for Douglas because within weeks of being released, he went right back to his bank-robbing ways,” FBI special agent Chris Hacker said in the release. “Thanks to the assistance of our partners with the Athens-Clarke County Police Department, he’ll have 20 more years to think about what he’ll do the next time he is released from prison.”

In addition to his 20-year sentence, Douglas was ordered to repay the $6,700 he stole from the Athens bank.

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