Chilling photo of would-be Trump shooter Thomas Matthew Crooks taken by sniper nearly an hour before attempted assassination

One of the final photos of would-be assassin Thomas Matthew Crooks shows the 20-year-old gunman crawling on the ground and seemingly scoping out a spot from which to shoot at former President Donald Trump nearly one hour before the attack.

The image was taken around 5:30 p.m. Saturday by a local police counter-sniper officer who reported that Crooks was a suspicious person on the grounds outside Trump’s rally in Butler, Pennsylvania, news station WXPI reported.

Crooks can be seen in the photo sporting long brown hair and glasses while wearing a gray T-shirt representing the popular YouTube gun channel Demolition Ranch . It was unclear in the picture if Crooks had a gun on him then.

Law enforcement sources told the station that the sniper, a member of the Beaver County Emergency Services Unit, searched the grounds for Crooks after sending the picture, but he had moved from the location where the picture was taken.

Around 5:45 p.m. — 26 minutes before the shooting — the same Beaver County cop spotted Crooks a second time, now on the roof, took a second picture and called it in to the command center.

New video shows would-be Trump assassin Thomas Matthew Crooks at rally an hour before he opened fire

At 6:11 p.m., Crooks fired the first shot at Trump from about 130 yards away, grazing his ear and killing one rally attendee. Two other people were seriously injured in the attack.

When Trump took the stage, Crooks was still on the ground and had not yet climbed onto the roof of the building , according to the local TV report.

He was spotted on the roof about seven minutes before the shooting, WXPI reported.

A local Butler Township police officer was hoisted to the roof of the factory moments before Crooks opened fire and confronted the gunman.

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The FBI plans to interview members of the Emergency Services Unit who were on the scene later this week, sources told the station.

Photos have also emerged of Crooks’ cellphone and a remote transmitter next to his dead body atop the manufacturing plant where he attempted to carry out the assassination.

A gray, 12-button remote and a “newer model” phone were recovered from the 20-year-old’s body after the shooting, according to photos obtained by WPXI.

The transmitter is believed to have been connected to an explosive device found inside Crooks’ car as investigators suggested that he had planned to stage a distraction during the shooting.

Crooks was spotted by law enforcement, using a rangefinder and looking at his phone, nearly an hour before Trump took the stage, though he first raised suspicions around 3 p.m. that day when he passed through the security screening area with the rangefinder.

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A rangefinder is a device similar to binoculars used by hunters and target shooters to measure distances for long-range shots.

Investigators’ working theory is that Crooks went to his car to retrieve the AR-style rifle he stole from his father, the outlet reported.

Seconds before Crooks took aim at Trump, a local cop interrupted the shooter , who pointed the rifle at him before the cop dropped and fell eight feet to the ground.

While the bullet only grazed Trump’s right ear, Crooks killed hero firefighter and father Corey Comperatore , who was at the rally with his wife and daughters.

The 50-year-old dad shouted “Get down!” and used his body to shield his family from the gunfire before he was fatally shot, his heartbroken wife told The Post from her Sarver, Pa., home Monday.

Two other rallygoers were also injured.

Authorities have not yet shared a possible motive for the shooting.

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