Horrifying video shows Trump fans pointing at shooter Thomas Matthew Crooks moments before he opened fire in Pennsylvania rally assassination attempt

New video emerged Sunday night showing Donald Trump's supporters outside the security perimeter pointing at the would-be assassin as he bear-crawled on the roof of a nearby building before opening fire on the former president.

A nearly 50-second clip showed rally goers who did not make it inside the Butler, Pennsylvania event looking, pointing and questioning why there was a man on the roof of an industrial building just 130 yards from the stage where Trump was speaking.

'Look, they're all pointing,' the man behind the camera is heard saying as it pans from the stage to the warehouse roof where a figure is seen crawling. 'Yeah someone's on top of the roof – look.'

'He's on the roof!' a woman yells 40 seconds into the video as Trump is heard in the background continuing his remarks.

Thomas Matthew Crooks, 20, was killed by U.S. Secret Service after his assassination attempt on Trump at his rally Saturday. 

New video emerged showing people outside the security perimeter of Donald Trump's Butler, Pennsylvania rally pointing and shouting about a man on a nearby roof that ended up being would-be assassin Thomas Matthew Crooks

One bullet clipped the former president's ear, but his campaign says he is otherwise 'fine.'

A turn of his head to look at the jumbotron where charts of immigration statistics were on screen may have saved his life, according to his aides and analyses of the bullet's path.

Former fire chief Corey Comperatore, 50, was killed in the crosshairs of the attack as he protected his wife and two daughters. David Dutch, 57, and James Copenhaver, 74, sustained critical injuries but are now listed as 'stable.' All three are Pennsylvania natives. 

The video showing a new angle of the shooter moments before he opened fire reads on screen, 'Plenty of time and opportunity to eliminate the threat,' as questions circulate over where the security failure was that allowed for the assassination attempt.

'There he is, right there. See him?' the camera man says as he points to the figure of Crooks laying on his side atop the building in the video obtained by deaf North Carolina-based journalist Annie Dance.

A handful of people are seen in the video standing in the shade and staring in the direction of the soon-to-be-shooter. 

Donald Trump's ear was clipped by one of Crooks' bullets at his Butler, Pennsylvania rally. Secret Service detail assisted him off stage as the former president pumped his fist and yelled 'fight'

Thomas Matthew Crooks, 20, of Bethel Park, Pennsylvania was killed by Secret Service seconds after trying to shoot Trump at his rally on Saturday

Crooks, who just graduated high school two years ago in the nearby community of Bethel Park, Pennsylvania, was immediately neutralized by the Secret Service seconds after the assassination attempt.

He used an AR-15 that his father legally purchased to carry out the attack.

The FBI is now investigating the crime and searched Crooks' family home where they found explosive materials as well as bombs in his vehicle, which was parked near the rally site in Butler, Pennsylvania on Saturday.

Congress wants to conduct their own investigation into the matter and specifically look at the security failures that may have allowed the attack to be carried out.