Fayetteville, N.C. — Two Cumberland County deputies have been fired following an internal investigation, Sheriff Earl "Moose" Butler said Friday.

Lt. Neelis Smith and Capt. Cuyler LaRue Windham Jr. were fired for their failure "to adhere to the high standards Sheriff Butler expects and requires of all Sheriff’s Office personnel," according to a statement issued by the office.

Officials said the circumstances that led to their firings are the subject of a criminal probe by the State Bureau of Investigation, and did not provide any other details.

The Associated Press and the Fayetteville Observer, however, learned that the SBI was investigating the deputies for their handling of off-duty jobs.

The Fayetteville Observer reported that the Cumberland County school system paid Smith more than $70,000 since 2005 to work off-duty security at sports games. At times, he was paid for working several games on the same night.

The Observer also reported that Smith and Windham had billed the Crown Center and the school system for working events on the same evenings.