Harrell managed to conceal his fraud for 11 years by preparing fake annuity account statements that were periodically presented to members, prosecutors said. They did not say how many members were affected by the fraud or how Harrell spent the members' funds.

Stacey Mills, president/CEO of Welcome, said the credit union purchased the branch from the $407 million Members Heritage in Lexington, Ky., in October 2016.

"As soon as Welcome Federal Credit Union learned of an impropriety, we investigated it and terminated his employment," he said. "The state and federal criminal authorities were alerted to the facts as we knew them. Welcome Federal Credit Union engaged a forensic accountant who scrutinized all related accounts and all accounts out of that branch so that we could understand the full scope of the matter and confirm that it was limited to Mr. Harrell's per se employment with Welcome. We're glad that justice was done yesterday in the matter."

Mills said Harrell's fraud was detected by the credit union's internal controls.

Although Harrell's plea agreement is listed on the federal docket, the district court in North Carolina has not made the document available online.