As various congressional committees ramp up efforts to investigate the attempted assassination of Trump, one House Republican is pushing for an independent commission modeled after the one that investigated the 9/11 attacks.

"I believe that we just need an independent, nonpartisan group to look at that like we did after 9/11 to make sure that this type of thing never happens again,” South Carolina Republican Rep. Jeff Duncan told NBC News. “This was an abysmal failure of the security detail that day to leave a rooftop in a building with line of sight to the stage and the podium unguarded and uncovered with security.”

Duncan acknowledged the investigatory efforts that have already been launched by the House Oversight, Homeland Security and Judiciary committees, but said there are limits to Congress’ ability to get answers through a typical committee hearing process where each lawmaker has just five minutes to ask questions.

That would be especially cumbersome given the number of potential witnesses Duncan envisions: the director of the Secret Service, the head of Trump’s detail, the advance team that prepared the site, Pennsylvania State Police, local law enforcement, Department of Homeland Security employees and other witnesses.

Duncan argued an independent commission with subpoena power would be better able to collect all that information. “I think it’s a way to get the answers that American people deserve, and we as elected officials deserve,” he said.

The former president has reached out to and spoken with a member of Corey Comperatore’s family, according to his sister Dawn Comperatore Schafer.

Comperatore, 50, a former fire chief, was attending the rally as a spectator when he was killed in the shooting.

Three U.S. officials briefed on the matter confirm that the U.S. obtained intelligence in recent weeks about an Iranian plot to assassinate Trump, and the information led the Secret Service to increase security around the former president.

The plot was first reported by CNN. The Secret Service did not immediately respond to a request for comment.

“Upon learning of the increased threat, NSC directly contacted USSS at a senior level to be absolutely sure they continued to track the latest reporting,” a national security official told NBC News.

Donald Trump Jr. said that after he learned that his father had been wounded, it took 90 minutes before he knew the former president was safe and could speak to him on the phone.

He told Axios during an interview at the Republican National Convention today that his father was surprisingly calm at first and injected some levity into the conversation despite the heaviness of the moment.

"How's the hair?" he said he asked his father.

"The hair is fine, Don," he said in an impression of his father. "The hair is fine. A lot of blood in it, but it’s fine."

After days of pressure from several Asian American organizations, the New York Post has apologized for initially misidentifying the Trump shooter as a “Chinese man.” 

The outlet added an editor’s note to its article on the shooting, explaining that its erroneous reporting had been “based on wrong information we obtained from sources.” 

“We quickly corrected the mistake. We sincerely apologize for the error,” the note said. 

Authorities identified Thomas Crooks, 20, who is white, as the shooter.

The correction comes after groups, including civil rights nonprofit Stop AAPI Hate and the Asian American Journalists Association called out the news outlet for not only the reporting error but failing to disclose the mistake for days. Many groups described the error as “dangerous,” potentially stoking anti-Asian sentiment. 

“This isn’t a harmless mistake, it’s reckless misreporting that is actively fueling dangerous misinformation and anti-Asian racism,” Stop AAPI Hate posted on social media. 

Following reports of a suspicious person, Butler Township police officers "boosted" one of their officers to gain a view of the rooftop where Crooks was, Butler Township Manager Tom Knights told NBC News.

Township police were stationed in the vicinity of the building, which to Knights' knowledge had no roof access from either inside or outside of the building. One officer held up another officer, who was able to grab ahold of the ledge, Knights said.

"So when he was able to pull his head up over the roof, he did in fact see an individual ... with a weapon," Knights said.

Crooks turned his weapon toward the officer, who Knights said was unable to reach his radio or firearm. The officer released his hands in a "defensive" move and dropped 8 feet to the ground, injuring his ankle.

According to Knights, three different security meetings were held prior to the rally, as early as July 8, and the building was mentioned in at least two of those meetings. He was not present but familiar with the conversation, and noted that the building was outside of the Secret Service’s established perimeter.

Reps. Jared Moskowitz, D-Fla., and Matt Gaetz, R-Fla., introduced a resolution honoring Corey Comperatore, who died shielding his family during the attempted assassination.

The resolution also condemns any form of political violence. Gaetz said the resolution will “commemorate” Comperatore’s bravery and his “unwavering commitment to public service.”

Moskowitz also highlighted Comperatore's bravery, saying: "He deserved the ability to go to a political rally and return home. I hope that my colleagues will join us in honoring his sacrifice."

A couple who witnessed Donald Trump’s would-be assassin shimmy along a nearby roof and set up his shot panicked for several minutes as they shouted for law enforcement intervention and watched as those efforts failed.

Mike DiFrischia, and his wife, Amber, said they flagged a nearby police officer as soon as they saw a man begin to Army crawl up the roof near the start of Trump’s presidential campaign rally Saturday in Butler, Pennsylvania.

“We started hollering to cops, ‘Hey, he’s right there!’ We could see him on the roof,” DiFrischia, 46, told NBC News.

DiFrischia said the officer, who was wearing all black with a police badge on his back, was too close to the building and could not see the shooter.

Trump was already speaking at this point, DiFrischia said.

The urgency rapidly grew when the man on the roof, later identified by authorities as 20-year-old Thomas Crooks, was a quarter of the way to the top, DiFrischia said. That’s when the crowd noticed he was holding a firearm.

“Next thing you know, somebody behind me said, ‘That guy’s got a gun!’ Everybody started running and freaking out,” DiFrischia said. “I moved over and I could see the gun with my own two eyes.”

DiFrischia said he watched a different uniformed law enforcement officer attempt to pull himself up on the roof that the gunman was on but quickly release when he got about chin level.

“As soon as he got pulled up on the roof, he just let go and fell down to the ground,” DiFrischia said. “I said, man something must have startled him.”

At that point, DiFrischia, an avid hunter with 40 years of firearm experience, said there was nothing else to do but pull out his phone and start recording.

“I knew he was now getting into position to shoot something,” he said. “I was like, my God, my heart dropped.”

His footage begins with Crooks lying on his stomach near the top of the roof. It ends with Crooks dead.

“I heard one shot and then it was bam, bam, bam, bam,” Amber said. “And then it was all over.”

A Texas YouTuber who runs a popular gun enthusiast channel is distancing himself from the gunman who opened fire on Trump.

Photos verified by NBC News show the shooter, identified by law enforcement as Thomas Matthew Crooks, wearing a Demolition Ranch shirt on the day of the shooting. The images began circulating after Crooks, 20, of Bethel Park, was killed by at least one Secret Service sharpshooter.

In a nearly six-minute-long video Monday, Matt Carriker, who runs the YouTube channel Demolition Ranch, said: “We were shocked and confused to find this out. The shooter who tried to assassinate Trump was wearing merch from my channel, wearing a Demolition Ranch T-shirt. And that sucked to see that.”

“Yeah, that was rough,” he added.

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