(emphasis mine)

Minor correction here - DCA is actually located in Arlington, VA, not the District of Columbia. It is also governed by a special governmental agency, the Metropolitan Washington Airports Authority, an agency of the Federal Government created under the Metropolitan Washington Airports Act of 1986, Title VI of Public Law 99-500. They are responsible for management of operations at DCA (Ronald Reagan Washington National Airport) and IAD (Washington Dulles International Airport). They maintain their own emergency services departments. The LEOs involved in this incident, should be (not easy to identify in the videos) members of the MWAA Police Department, not the Metropolitan Police Department of the District of Columbia.