A House staffer who was arrested Friday for bringing a gun into the Cannon House Office Building says that the incident was an “accident.”

NBC4 reports that Ryan Shucard—a press secretary for Rep. Tom Marino (R-Pa.)—entered a not guilty plea in a D.C. Superior Court on Saturday, with his lawyer saying that the whole thing “was a total accident.”

On Friday, Shucard was arrested when a conveyor belt bag check at security checkpoint at the Cannon Building revealed there was a 9mm Smith & Wesson firearm and magazine in his bag. Shucard was arrested and charged with a felony for carrying a pistol without a license, a U.S. Capitol Police public information officer told DCist.

Shucard was indefinitely placed on an unpaid administrative leave by his office upon his arrest. Bill Tighe, Rep. Marino’s chief of staff, tells NBC4 that they’re “disappointed in Ryan’s lack of judgement.”