The United States Park Police is warning Occupy DC protesters that they must stop camping at two parks by noon on Monday or risk arrest. The National Park Service distributed warning fliers to protesters on Friday at McPherson Square on K Street and at Freedom Plaza on Pennsylvania Avenue. The move comes after a hearing on Tuesday of the House oversight subcommittee whose portfolio includes the District of Columbia, at which Republican lawmakers questioned why camping has been allowed at the parks since October. The park service said it has a history of accommodating 24-hour vigils and protests. The flier distributed Friday defines camping as using land for “living accommodation purposes such as sleeping” and says camping materials must be removed and temporary structures left open for inspection.