(NewsNation) — Why did Thomas Matthew Crooks try to kill former President Donald Trump? Crooks’ motive remains a mystery nearly two weeks after he was able to get off several shots, killing one spectator, seriously wounding two others and nicking Trump in his right ear.

Though law enforcement officials and Crooks’ relatives have said nothing that might shine a light on his motive, a few facts have come to light, thanks to the testimony of FBI Director Christopher Wray to the House Judiciary Committee earlier this week.

Investigators found pictures of Trump on Crooks’ phone, as well as those of President Joe Biden, Attorney General Merrick Garland and Wray himself.

Investigators also say Crooks researched the dates of the Democratic National Convention, to be held next month in Chicago, as well as scheduled appearances by Trump.

“On July 6, he did a Google search for ‘how far away was Oswald from Kennedy,’” Wray said in testimony before a House committee. He called that search “significant” regarding Crooks’ state of mind.

Wray said July 6 was also the date when Crooks registered to attend the Trump rally in Butler, Pennsylvania.

“He was interested in public figures,” Wray said, adding that it was around July 6 when Crooks began focusing on the Butler rally.

That focus turned into reconnaissance missions, as Crooks visited the rally venue six days ahead of the July 13 event.

Crooks, who worked as a food service worker at a nursing home and had no criminal record, asked his bosses for permission to take July 13 off. And, on that day, he bought the ammunition he used in the shooting from a gun store a few miles from his home.

He also flew a drone over the Bulter Farm Show property hours before the rally. Police found remote-controlled explosive devices in Crooks’ car, but the homemade bombs were left in the “off” position.

“We’ve recovered three devices: two in his vehicles, and one back in his residence,” Wray said at the House hearing. Wray called them “relatively crude devices” that were capable of remote detonation. He said the bombs had receivers attached, and Crooks had a transmitter with him at the time of the shooting.

Wray also told lawmakers they believe that Crooks acted alone.

“So far, we have not found any evidence of accomplices or co-conspirators, foreign or domestic,” he said.

A senior congressional source told NewsNation that Crooks had a “major depressive disorder” diagnosis. His high school classmates said Crooks was a loner and was ridiculed for how he dressed.

“He was bullied so much,” said one former classmate.