PHOENIX (AP) — An 82-year-old man who spent most of his adult life behind bars for robbing banks was convicted again for carrying out an armed heist at an Arizona credit union as he struggled to adjust to life outside prison.

Robert Francis Krebs faces a maximum 25 years in prison after a jury found him guilty Wednesday of armed bank robbery. The January 2018 holdup in Tucson came about seven months after he was released from prison.

Krebs served more than 30 years for a 1981 bank robbery in Florida and was sentenced to three years in prison after a 1966 conviction in Chicago for embezzling $72,000 from a bank where he worked as a teller.

He also served an additional 17 years for theft and armed robbery convictions from Arizona dating to 1980.

In the Florida robbery, the branch manager and teller tripped a silent alarm and were later put in the bank vault. Krebs, who was arrested as he walked into the bank's parking lot, was disguised in a wig, had cotton in his cheeks and varnished his fingertips to leave no fingerprints, according to news accounts by The Orlando Sentinel.

Krebs' attorney, Leonardo Costales, didn't immediately return a phone call and email Friday seeking comment on his client's latest conviction.

Krebs told investigators that he didn't wear a disguise in the 2018 Tucson robbery because he wanted to get caught and return to prison, according to court records.

Documents say he also told authorities that he committed the robbery because his monthly $800 Social Security payment wasn't enough to live on and that the months before the robbery were the worst in his life.

Last summer, a judge ruled Krebs was mentally fit to stand trial despite his claim that he has symptoms of Alzheimer's disease.

Two mental health experts said Krebs was mentally competent and believed he was malingering, with one expert saying Krebs had "embellished or grossly exaggerated" his condition to avoid prosecution.

The judge who declared Krebs psychologically fit said he was able to meticulously tell FBI agents how he planned and carried out the robbery.

Prosecutors said Krebs decided the credit union was an easy target because there was no glass separating customers and tellers and that he picked a lending institution near a mall, where it would be harder for police to find him.

Authorities said Krebs walked into a Pyramid Federal Credit Union branch on Tucson's northern edge, put a handgun that turned out to a BB gun on the counter and demanded cash.

Authorities say he walked away with nearly $8,400 and later told investigators that he almost got struck by a vehicle while crossing a roadway. He was later arrested at a hotel.

Bank robbery experts say it's unusual for older people to hold up lending institutions. Typically, bank robbers are in their 20s.

J.L. Hunter "Red" Rountree, who has been dubbed America's oldest bank robber, was convicted of committing two robberies in his mid-80s and was 91 at the time of his last heist in the early 2000s. He robbed banks in Mississippi, Florida and Texas.

Rountree died in prison at age 92.