REVEALED: Details emerge about how 'suspicious' Trump shooter evaded officers posted at second-story window overlooking roof and which unit was responsible for building security

The US Secret Service left security for the building from which would-be assassin Thomas Matthew Crooks, 20, was able to shoot former President Donald Trump and kill a campaign rally attendee in the hands of a local police unit, it has been revealed.

Pennsylvania State Police Commissioner Col. Christopher Paris testified to Congress Tuesday that the Butler County Emergency Services Unit was responsible for the building's total security.

He also revealed shocking details about the series of events that unfolded leading to the shooting.

Paris said two law enforcement officers from the emergency unit were stationed at a 'second-story' window above the roof where Donald Trump's shooter opened fire. 

Those officers reported Crooks as 'suspicious' as he wandered near the security perimeter and pulled out a range finder, but then abandoned their post to look for him on the ground. 

That bungling move provided a window of opportunity for Crooks to climb up onto the roof without initially being spotted.

The emergency unit is comprised of local officers from across multiple Pennsylvania counties, Paris said. 

The officers first identified Crooks as suspicious after seeing him roam around the campaign rally without entering the event, he went on.

They saw him from the second-story window overseeing the roof from where Crooks shot, Paris testified.

Then, when Crooks produced a range finder, their concerns were heightened further and they left their post at the window to go find the suspect - leaving the roof unguarded.

'I am aware that two were in the building,' Paris responded to questions about whether law enforcement officers were near the location from where Crooks opened fire. 

'I was told they were in a window,' he continued. 

The Pennsylvania State Police Commissioner then revealed that it was these two officers who initially reported Crooks as 'suspicious.'  

'I was told at a certain point they began searching along with other local officers in the immediacy after Crooks had been identified as suspicious by them.'

'By them?' Rep. Dan Bishop, R-N.C., questioned.  

'My understanding is that they identified Crooks,' Paris responded.

'Crooks never made it through the secure perimeter into the venue space itself,' he said, which raised alarm among the two officers who spotted him, prompting them to mark him as suspicious. 

'He was identified by those members as suspicious, in part, because of that. And then at some point he produced the range finder which heightened that suspicion.' 

Nine days after Trump was shot by Crooks, lawmakers and Americans still have plenty of unanswered questions about how the near assassination attempt was able to proceed unabated. 

On Monday, a group of lawmakers on the committee traveled to Butler, Pennsylvania, to investigate the area of the shooting. 

Rep. Eli Crane, R-Ariz., later posted a video of the second-story window to which the agents had access. 

Playing Crane's video during the hearing, Bishop sought to clarify whether the window in the video is the same on from where the officers first denoted Crooks as a person of interest. 

'That window was open,' after the shooting, Bishop said.

'Was it from this vantage point that those ESU officers spotted Crooks?' 

Paris responded: 'I don't know that particular window, but my understanding is from a second-story window is where he was initially spotted.'

The back and forth revealed that the officers had been stationed overseeing the roof from where Crooks shot, but before he opened fire, they left that location to search for him. 

While Secret Service Director Kimberly Cheatle spent Monday ducking questions from Congress during a hearing about Donald Trump's near assassination at a campaign rally in Butler, Pennsylvania, some top Republicans were actually investigating the scene of the crime. 

'I'm standing at approximately the site where the shooter was,' Rep. Carlos Gimenez, R-Fla., another member of the committee, said standing on the roof of the building where 20-year-old Thomas Crooks shot Trump.  

'As you can see I am a 70-year-old man and this roof is not a big deal,' he said in an apparent rebuke of Cheatle's excuse that Secret Service agents were not stationed on the building because of its 'slope.'

'So for somebody to tell me that Secret Service couldn't have been here, that's crazy,' he said while filming the vantage point. 'You can see that you've got a clear line to the president. It's not a hard shot.' 

Cheatle doubled down on her bizarre excuse for not putting Secret Service agents on the roof where Gimenez was standing during her testimony before the House Oversight Committee on Monday. 

The director explained agents were not stationed there because the agency generally 'prefers sterile rooftops.' 

'When we are providing 'overwatch' whether that be through counter snipers or other technology, [we] prefer to have sterile rooftops,' Cheatle said.

The disgraced Secret Service director resigned Tuesday after her horrendous congressional testimony.  

The hearing Tuesday, however, was void of any high ranking officials, noticed by the Chair Mark Green, R-Tenn., who slammed the Secret Service, the FBI and Department of Homeland Security (DHS) for not sending anyone to answer lawmaker's questions.

'Unfortunately and unacceptably they have refused to appear before the committee today,' Green said of the missing attendees Tuesday. 

He said that he and the American people deserve answers to the historic tragedy and that a staggering amount of questions remain unsolved 10 days after the fact. 

'Why was the roof top which the shooter fired multiple rounds not secured?'

'Who made the decision not to post the counter sniper personnel on the roof?' 

'Why was nothing done to respond?'

'How did the shooter access the roof top despite reported federal and local law enforcement presence in and around the building?'