'Chilling' last picture of Donald Trump shooter shows Thomas Matthew Crooks just hours before moment

Thomas Matthew Crooks, the 20-year-old who attempted to assassinate former President Donald Trump on Saturday, arrived at the campaign rally in Butler, Pennsylvania three hours before his attack began, with a chilling photo showing his final moments .

Security measures at the event have come under scrutiny as Crooks reportedly drew attention for carrying a rangefinder , often used by hunters to measure distances for a long-range shot.

Crook, originally from Bethal Park, Pennsylvania, he fired eight rounds with an AR-15 rifle from a building rooftop beyond the security perimeter, hitting the former president in his right ear during the rally. He was familiar with guns, but was banned from his rifle club for quite an ironic reason .

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The gunfire also hit three other attendees. Corey Comperatore, a 50-year-old local firefither was killed, and two others, David Dutch (57) and James Copenhaver (74), were critically injured.

It's been reported that Crooks had asked to take the day off work on Saturday because he had "something to do," with his request being revealed by multiple law enforcement sources to CNN, reports the Express US .

His chilling words to co-workers were that he "would be back to work on Sunday."

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CNN also reported that the would-be assassin was spotted around 3:00pm on Saturday at the rally's security screening area, attempting to move through metal detectors while carrying a rangefinder.

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