The Secret Service is one of the country’s oldest federal investigative agencies, founded in 1865 to stop counterfeiters. There are approximately 3,200 special agents and an additional 1,300 uniformed officers who guard the White House, the Treasury building and foreign diplomatic missions in Washington.

The U.S. Secret Service marks its 160th anniversary, reflecting on its evolution from fighting counterfeiting to presidential protection.

One year after the attempted assassination of now-President Donald Trump at a campaign rally in Butler, Pennsylvania, the motives of shooter Thomas Matthew Crooks remain elusive, even as more details have emerged.