Federal prosecutors say 44-year-old Jesse Keel pleaded guilty Friday to a misdemeanor threat charge.
Authorities say Keel told a member of U.S. Rep Allyson Schwartz's staff that he was an ex-Marine who could jump on a bus and shoot everyone in the office.
They believe he made the Aug. 25 call from a Philadelphia hospital. The plea agreement says the staff had previously dealt with Keel.
Keel faces up to a year in prison and a $100,000 fine when he is sentenced May 23.
His public defender did not immediately return a call for comment.
