New photo of Trump shooter Thomas Matthew Crooks emerged shortly before the assassination attempt

A new image emerged on Friday showing Donald Trump's would-be assassin sitting on a wall and staring at his phone, showing the moments before he made his attempt to kill the ex-president.

Thomas Matthew Crooks sits on a wall on a lawn at the Butler Farm Show Grounds in Butler, Pennsylvania, on July 13 as he waits for Trump, 78, to take the stage.

In the image above, 20-year-old Crooks appears to be tapping on his cellphone, which was found next to a remote transmitter after he was killed by return fire from a Secret Service sniper.

In the photo, the shooter is wearing the same gray influencer-branded T-shirt he wore in the only other previously released photo of Crooks leading up to the shooting that killed retired fire chief Corey Comperatore, 50, and seriously injured David Dutch, 57, and James Copenhaver, 74.

The new image was released Saturday by Judicial Watch along with documents detailing how local police forces were deployed in preparation for the rally.

Not long after the snapshot was taken, Crooks climbed a nearby building and crawled into his final position, rifle in hand, to prepare for the shot.

The killer was on law enforcement’s radar long before his assassination: A local police officer took two photos of the “suspicious person” as she was looking for the perfect place to open fire.

Nearly an hour before Trump took the stage, Crooks was observed by an officer using the rangefinder and looking at his phone – an encounter that may have led to the now-released photo.

Despite all the suspicions, Crooks managed to draw his gun and fire eight shots at Trump before he was killed.

The shooter narrowly missed Trump – instead, shrapnel grazed the ex-president’s ear.

More than a month after the shooting, the shooter's motive is still unknown.