PORTLAND — A Lisbon Falls man who pleaded guilty to robbing a bank last year was sentenced to nearly four years in prison.

Randy Krog, 32, entered a guilty plea in January to a one-count grand jury indictment charging him with robbery in connection with an Oct. 13 bank robbery at Androscoggin Savings Bank on Lisbon Street in Lisbon Falls.

U.S. District Judge D. Brock Hornby sentenced Krog on Tuesday to 46 months in prison plus three years of supervised release. Krog also must be enrolled in a 500-hour drug treatment program while in prison. He’s required to pay a $100 special assessment and $768 in restitution to the bank, along with $270 with his wife, Denise, who pleaded guilty in February to bank theft. She is scheduled to be sentenced next month.

He has been held as a federal prisoner in Portland since his December indictment.

Krog was arrested at his apartment by Lisbon police on a charge of armed robbery the night of the bank robbery. Court papers said he entered the branch bank earlier that day, demanded money and fled with about $3,030.

The robbery was reported shortly before 1:30 p.m. He was in police custody by 9 p.m.

The U.S. Attorney praised the efforts of Federal Bureau of Investigation and Lisbon Police Department.

Some of the money, along with items used in the robbery, including gloves and a hat, were recovered where they had been discarded in Bowdoin.

A prosecutor’s memo filed in U.S. District Court said Krog wore a dark-colored ski mask with cut-out eye holes. He also wore a sweatshirt and yellow gloves. He carried a red-handled flare gun in his pocket.

He approached a bank teller, handed her a white plastic bag and told her to put money in it. The teller put the money in the bag, including five $20 so-called “bait” bills, and handed the bag to Krog. He left the bank.

In a written statement, Krog admitted to the robbery, prosecutors said. He said he gave $300 of the illicit cash to his wife. He led police to a river and showed where he had discarded his disguise.

After getting a search warrant, police found $2,100 in cash, including the “bait” bills, in the pocket of Krog’s jacket.