CHICAGO – A veteran Illinois state senator was arrested Wednesday after allegedly trying to board a flight from Chicago to Washington with a gun and ammunition in a carry-on bag, authorities said.

Sen. Donne Trotter, a Chicago Democrat who recently announced he would run to replace Jesse Jackson Jr. in the U.S. House, was carrying an unloaded .25-caliber Beretta handgun and a magazine clip with six bullets when he tried to board a flight at O'Hare International Airport, according to Chicago police.

Trotter, who is part the Illinois Senate's Democratic leadership, was charged with a felony.