Trump shooting updates: Shooter flew drone near site hours before shooting

The shooter, Thomas Matthew Crooks, accessed the roof of the AGR building using mechanical equipment on the ground and piping on the side of the building, FBI Director Christopher Wray told the House Judiciary Committee.

Crooks visited a gun range a day before the shooting, Wray said.

Authorities have interviewed Crooks’ parents, who Wray describe as "cooperative."

"It's the FBI position right now that he still acted independently," he said.

Wray said he was about to have dinner with family when he heard about the shooting. He said he was "horrified and angry."

-ABC News’ Luke Barr

It appears the shooter, 20-year-old Thomas Matthew Crooks, was a "loner" and didn't have a lot of contacts in his phone, FBI Director Christopher Wray told the House Judiciary Committee.

"A lot of people describe him as a loner. That does kind of fit with what we're seeing in his devices, you know, his list of contacts, for example, is very short, compared to what you would normally see from most people. Doesn't appear to be a whole lot of interaction between him, you know, face-to-face or digital, with a lot of people," Wray said.

The FBI has conducted over 400 interviews, with "many more to conduct," he said.

-ABC News’ Luke Barr

The weapon used by the gunman had a "collapsible stock," meaning Thomas Matthew Crooks could easily conceal the gun at the rally, FBI Director Christopher Wray told the House Judiciary Committee.

"The weapon had a collapsible stock, which could explain why it might have been less easy for people to observe," he said.

Wray said that the shooter was not on the FBI's radar and there were no FBI assets at the rally.

Wray said there were 14 guns in the home where Crooks lived.

-ABC News’ Luke Barr

Starting on July 6, the gunman, Thomas Matthew Crooks, became "very focused" on former President Donald Trump and the rally in Butler, Pennsylvania, FBI Director Christopher Wray told the House Judiciary Committee.

"On July 6, he did a Google search for, 'How far away was Oswald from Kennedy?'" Wray said.

The shooter went to the rally site a week before the assassination attempt and spent about 20 minutes there, Wray said.

"Then he went to grounds again on the morning of the event, it appears, for about 17 minutes," Wray said.

Crooks went to the site a third time "for good,” Wray said.

-ABC News’ Luke Barr