Incredible details are revealed from ‘one-in-a-million’ sniper shot that took down Trump shooter Thomas Matthew Crooks

The Secret Service agent who killed Donald Trump’s assassin fired a “one-in-a-million” shot to the head, an investigator says.

Thomas Crooks was hidden behind the edge of a building’s roof, more than 450 feet from where the protection unit was stationed during the July 13 meeting in Pennsylvania.

The officer had only the sights of the 20-year-old weapon and a few square inches of his forehead to aim at as his colleagues rushed to remove the wounded ex-president from the podium.

But the officer killed the gunman with a single shot after a local tactical team fired and missed, a source close to the investigation told Fox News.

The trigger was pulled seconds after the Crooks fatally shot Pennsylvania Fire Chief Corey Comperatore, seriously wounded two others and struck Trump in the right ear after he scaled a building 440 feet (135 meters) away.

The agent had only the sights of the 20-year-old weapon and a few square inches of his forehead to aim at as Secret Service colleagues rushed to remove the wounded ex-president from the stage.

“They were watching him as he was watching them,” a senior federal law enforcement official told CNN on Wednesday.

Bystander video of the moment shows Crooks peering intently through the scope of his father’s AR-style weapon and firing toward the crowd as onlookers shout from the base of the building.

Immediately there was a return shot and Crooks lay dead on the roof, while the people on the ground gasped in horror.

“The Secret Service shouldn’t mess with people,” someone shouted. “Holy shit.”

The former president praised the Secret Service agents who came to his aid in his speech at the RNC on Thursday night.

“They are incredible people,” he told delegates. The Secret Service agents put themselves in harm’s way.

‘The bullets flew right over them, narrowly missing them. And then it all stopped.

“Our Secret Service sniper, from a much greater distance and with only one bullet, took the life of the assassin. He took him out.”

Thomas Crooks was shot and killed by Secret Service agents on the roof of the police station, just 450 feet from where former President Donald Trump spoke Saturday night.

Trump clutched his right ear as the first shots rang out at 6:12 p.m.

As Trump raised his fist to the crowd, some were heard cheering his name and chanting “USA” and “Make America Great Again”

Secret Service Director Kimberley Cheatle said it was decided not to put agents on the roof of the building where Crooks was stationed because it had a “sloping roof.”

But the praise for agents on the ground stands in stark contrast to the anger directed at Secret Service Director Kimberley Cheatle, who was chased through the halls of the RNC convention hall by angry senators Wednesday night demanding answers.

She was in Milwaukee’s Congressional Hall to oversee security measures just hours after she placed a call with senators asking for her protection from the shooting in Pennsylvania on Saturday night.

Senators John Barrasso of Wyoming and Marsha Blackburn of Tennessee led the chase, complaining that they did not have a chance to ask Cheatle their questions during the phone call.

A frustrated Barrasso then issued an ultimatum to the security chief.

“You almost killed him,” Barrasso shouted at Cheatle. “So resign or full explanation.”

She is scheduled to appear before the House Committee on Oversight and Accountability at 10 a.m. Monday after more details emerge about how Crooks was able to wander around the Butler meeting site for hours without incident, despite repeated warnings from the public.

The building he climbed over was guarded by local police, who deemed it too dangerous to place an officer on it because of the sloping roof.

According to reports, three police officers from neighboring Beaver County were stationed in the building when Crooks climbed onto the roof and fired his volley of at least six shots from inches above their heads.

The Wall Street Journal reported Thursday that the killer had even flown a drone over the scene hours before the shooting.

Cheatle is expected to answer questions during a highly anticipated House Committee on Oversight and Accountability hearing at 10 a.m. Monday

Crooks reportedly flew the drone on a programmed flight path. Officials say the predetermined path suggests Crooks flew the small aircraft more than once to scout the location of the demonstration.

Secret Service spokesman Anthony Guglielmi stressed in a statement Wednesday evening that his boss would not resign.

“Continuity of operations is of the utmost importance during a serious incident, and U.S. Secret Service Director Kimberly Cheatle has no plans to resign,” he said.

“She has great respect for the members of Congress and is deeply committed to transparency in the conduct of the Secret Service during its internal investigations, and she strengthens the service through the lessons learned during these important internal and external reviews.”