Attempted Trump assassin seen walking around Pennsylvania rally hours before opening fire

Chilling new video has been released showing Thomas Matthew Crooks casually walking through a crowd in Butler, Pennsylvania, nearly two hours before he opened fire on former President Donald Trump and attendees at a campaign rally. 

The short clip, released by the clothing company Iron Clad USA, shows Crooks at 4:26 p.m. dressed in shorts and a "Demolitia" T-shirt walking past a line of vendors selling Trump merchandise ahead of the July 13 rally. 

He was wearing the same T-shirt when he opened fire on Trump and is not carrying anything in the eerie video. 

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Chilling new video has been released showing Thomas Matthew Crooks casually walking through a crowd in Butler, Pennsylvania, nearly two hours before he opened fire on former President Trump and attendees at a campaign rally.  (Anna Moneymaker/Getty Images, main, and Iron Clad USA, inset.)

Crooks later climbed onto the roof of the nearby AGR building and fired eight shots, with one bullet grazing Trump's right ear. One attendee, Corey Comperatore, was fatally struck, while two others were also hit and suffered serious injuries.

"The U.S. Secret Service is aware of and reviewing a variety of footage from July 13 as part of our mission assurance review," the Secret Service said in a statement in response to news of the new footage being released. 

"The U.S. Secret Service is committed to examining the processes, procedures, and factors that led to this operational failure, so that we can ensure it never happens again."

Pictures of Thomas Mathew Crooks taken by a sniper. (Sen. Ron Johnson's Office)

A preliminary report released by Rep. Clay Higgins, R-La., last week found that all eight shell casings were recovered and are in proper possession of the FBI. Higgins said that Crooks’ position on the roof of the AGR building provided him with excellent concealment from the northern counter-sniper team due to the foliage and branches of two trees.

One shot was fired by a Butler SWAT operator from the ground, about 100 yards away from the AGR building. The shot hit Crooks’ rifle stock and fragged his face and shoulder area from the stock breaking up, Higgins said.

Police standing over Thomas Crooks after he was shot (Butler Township Police Department)

Higgins believes this shot damaged the buffer tube on Crooks’ rifle, meaning that the rifle would not have fired after his eighth shot.

Audrey Conklin is a digital reporter for Fox News Digital and FOX Business. Email tips to This email address is being protected from spambots. You need JavaScript enabled to view it. or on Twitter at @audpants.