EXCLUSIVE: PITTSBURGH — A video from James Copenhaver, one of the victims critically wounded in the July 13 assassination attempt against former President Trump, shows a figure moving across the roof of the American Glass Research (AGR) building just minutes before gunfire rang out at Trump's rally in Butler, Pennsylvania.
In the video taken at 6:08 p.m. on July 13, the person appears on the roof of the building adjacent to where Trump is speaking and can be seen walking from the 1:00 second mark to about the 2:50 second mark.
Officials believe gunman Thomas Crooks, 20, began shooting with a collapsible AR-15-style rifle three minutes later, around 6:11 p.m. Counter snipers fatally shot Crooks shortly afterward, and law enforcement officials found eight shell casings near his body.
In his attempt to assassinate the former president, Crooks killed 50-year-old Corey Comperatore, a husband, father and former fire chief at the Buffalo Township Volunteer Fire Department. Crooks also critically wounded Copenhaver, 74, and David Dutch, 57. Both victims were shot twice, according to those familiar with both victims.
Copenhaver was not filming when he was shot, said his lawyer, Joseph Feldman at the Law Offices of Max C. Feldman. Feldman said Copenhaver stopped filming when everyone turned their heads to look at a projection screen.
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Copenhaver was discharged from Allegheny General Hospital on July 26 but is still recovering in a rehabilitation center, Feldman told Fox News Digital on Wednesday.
The first injury Copenhaver sustained was to his arm and the second was to his abdominal area, Feldman said.
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Trump and his rally attendees turned their heads to look at immigration statistics that had just been projected onto a large screen as the first shots rang out.
"He had almost seen or heard something whiz past him, which we're assuming was a bullet. He felt it on his arm, and he looked down at his arm…and felt pain initially, but he hadn't even realized he had been shot a second time at that point. It could have been shock," Feldman said of Copenhaver.
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Screaming and "pandemonium" ensued, and it took Copenhaver some time to realize what had happened to him.
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FBI officials told reporters during a press call on Monday that Crooks gained access to the roof of the AGR building by climbing HVAC equipment and piping. He then traversed multiple rooftops before he found his position on top of the AGR building, where he had a direct line of sight to the former president.
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Leading up to the shooting, on July 6, Crooks, of Bethel Park, Pennsylvania, researched how far Lee Harvey Oswald was from the late President John F. Kennedy when Oswald assassinated the former president in 1963.
On July 7, he traveled to the rally site and spent approximately 20 minutes in the area, according to Kevin Rojek, special agent in charge at the FBI's Pittsburgh field office.
On the day of the rally, Crooks parked his vehicle and flew a drone between about 3:50 p.m. and 4 p.m. about 200 yards from where the former president would be speaking on July 13. FBI Director Christopher Wray testified during a July 17 congressional hearing that Crooks had been at the rally site for about 70 minutes the morning of the assassination attempt.
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Law enforcement officials were also aware of a suspicious person near the rally site approximately 90 minutes before gunfire began and took photos of Crooks around 4:36 p.m.
The FBI is still working to determine Crooks' motive behind the shooting.
Fox News' Julia Bonavita contributed to this report.