A Florida man is under arrest after police say he brought unregistered guns and ammunition onto the grounds of the U.S. Capitol Building, AP reports.

U.S. Capitol Police spokesman Shennel Antrobus says officers confronted 59-year-old Ty Carroll Mitchum, of Clearwater, Fla., outside the building on Sunday because they thought he was acting suspiciously.

According to Antrobus, Mitchum told police he had guns in his car and allowed officers to search it. Police say they found three unregistered firearms, which are illegal in the District of Columbia, and ammunition, AP reports.