WASHINGTON — The gunman who attempted to assassinate former President Donald Trump reportedly flew a drone ahead of a rally in Pennsylvania to scout the location before the event, a law enforcement official said Saturday.

The drone was recovered by the FBI, which is leading the investigation into Saturday’s shooting at a gathering by 20-year-old Thomas Matthew Crooks.

Crooks fired multiple rounds from the roof of a building adjacent to the Butler Farm Show grounds, where Trump was speaking, before he was fatally shot by a Secret Service sniper. The existence of the device and its use at some point before the shooting could help explain why Crooks knew to fire from point-blank range.

The official who described the drone was not authorized to discuss the matter publicly and spoke to The Associated Press on condition of anonymity. Details of the drone were first reported by The Wall Street Journal.

Trump said this week that a bullet hit his right ear. A memo released Saturday by the Trump campaign and written by Texas Rep. Ronny Jackson, who served as the GOP White House candidate’s physician, said Trump suffered a gunshot wound to his right ear from a high-powered rifle that “came less than a quarter inch from his head and struck the top of his right ear.”

One of the bullets aimed at Trump killed 50-year-old firefighter Corey Comperatore, a spectator in the stands. Two others were seriously wounded.

The FBI continues to investigate what may have motivated Crooks to carry out the attack. So far, officials have found no ideological leaning that could explain his actions.

Investigators who searched his phone found photos of Trump, President Joe Biden and other senior administration officials, and also discovered that he had looked up the dates of the Democratic National Convention and Trump’s appearances. He also searched for information about major depressive disorder.

More details about the investigation are expected to be released next week when FBI Director Chris Wray appears before the House Judiciary Committee.

Associated Press editor Jill Colvin contributed to this report.