SOUTH BEND, Ind. (AP) — A northern Indiana man has pleaded guilty to a charge of threatening a federal employee in a telephone altercation with an aide to then-U.S. Congressman Joe Donnelly.

Forty-eight-year-old Brett Keiling of Granger entered the plea Friday before U.S. District Judge Robert Miller Junior in South Bend.

Keiling was arrested in January 2011 after he threatened to stab members of Donnelly’s staff during a phone call to the congressman’s South Bend office.

Keiling at one time was found incompetent to stand trial and was hospitalized.

His sentencing now is scheduled for April 15th.

Donnelly was elected to the U.S. Senate in November.