AUGUSTA — A Maine man has pleaded not guilty in federal court to charges that he threatened to kill President Barack Obama and U.S. Rep. Chellie Pingree.

The Kennebec Journal reports 66-year-old Peter M. Hamilton of Augusta was ordered held in federal custody after his arraignment on Thursday in Bangor. A six-count indictment says Hamilton made a series of threats targeting Obama and Pingree.

Two charges of threatening to kill the president carry maximum terms of 10 years of imprisonment. Four charges of threatening to kill Pingree carry maximum five-year terms.

A federal prosecutor says Hamilton is currently being held in state custody through a civil commitment process.