A string of security failures led to a gunman being able to fire multiple shots at former President Trump, killing a retired fire chief and wounding two others at a campaign rally in Butler, Pa., according to law enforcement sources.

Although armed security personnel responded swiftly, rushing a bloodied Trump off the stage after Saturday’s assassination attempt, questions about security flaws are mounting.

Among the issues that have been exposed in recent days:

• How the gunman was able to gain access to the roof of a nearby building and why authorities were not able to stop him before he opened fire: The building was meant to be covered by local law enforcement because it was not in the immediate vicinity of the venue, according to law enforcement sources not authorized to speak publicly about the investigation. The details of how the U.S. Secret Service and local authorities divided tasks for the rally remain unclear.
• When authorities learned of the threat: Videos show that some in the crowd noticed the gunman and tried to get the attention of law enforcement at least a minute before he fired at Trump. Local police say an officer got onto the roof just before the shooting but had to retreat because the gunman moved to shoot at him.
• Whether Secret Service sharpshooters could have fired on the gunman before he launched his attack: Videos from the rally show Trump standing at a lectern with two Secret Service snipers positioned on a rooftop in the background. In the seconds leading up to Trump’s being struck by gunfire, the snipers can be seen looking through a scope and adjusting their rifles before firing. Investigators also are examining those tactics, according to law enforcement sources not authorized to discuss the inquiry.

Twenty-year-old Thomas Matthew Crooks shot at the former president with an AR-style rifle from more than 450 feet away. A bullet grazed Trump’s ear before Secret Service snipers returned fire and killed Crooks a few seconds after.

Federal officials have defended the Secret Service while acknowledging security failures at the rally.

An FBI investigation is underway, and an independent review will be conducted on the Secret Service’s actions at the campaign event, Homeland Security Secretary Alejandro N. Mayorkas said during a news briefing Monday.

A person not authorized to discuss the investigation said that Crooks’ father purchased the rifle in 2013 and that Crooks purchased about 50 rounds from Allegheny Arms & Gun Works in Bethel Park, Pa., on the morning of the shooting.

Steve Gordon, a retired Los Angeles Police Department SWAT team sniper who reviewed social media video of the shooting, said he saw a slight delay before Secret Service snipers fired on Crooks. Gordon said the delay was caused by the agent trying to find his target.

The investigation also is examining communications between local police and the Secret Service.

Despite public criticism of security at the rally, Mayorkas offered his support to the Secret Service and its leadership.

“What you saw onstage on Saturday, with respect to individuals putting their own lives at risk for the protection of another, is exactly what the American public should see every single day,” Mayorkas said, referring to the agents who surrounded Trump after he was shot.

In an interview with ABC News on Monday, Secret Service Director Kimberly Cheatle said the shooting “was unacceptable” and “something that shouldn’t happen again.”

“It was obviously a situation that as a Secret Service agent, no one ever wants to occur in their career,” she said. “The buck stops with me.”

Cheatle said local police were inside the American Glass Research building where Crooks was positioned.

“There was local police in that building. There was local police in the area that were responsible for the outer perimeter of the building,” she said.

Cheatle said the Secret Service shared support for the building where Crooks was as well as the inner perimeter at the rally site.

“And then we sought assistance from our local counterparts for the outer perimeter,” she added.

People take cover after former President Trump is shot during a campaign rally in Butler, Pa., on July 13, 2024.

(Evan Vucci / Associated Press)

Mayorkas said it’s not unusual for the Secret Service to rely on other law enforcement agencies during a presidential campaign to fill out tasks, noting that is especially true for the Trump campaign.

“We draw upon resources not only across the federal government, but with state and local law enforcement,” he said.

Mayorkas declined to comment on specifics of the security detail or communications between the Secret Service and local law enforcement.

The Pennsylvania State Police said in a statement that the Secret Service requested 30 to 40 of their officers to assist in securing the rally’s inner perimeter Saturday.

The agency said securing the property and building where Crooks was perched on the roof was not part of the officers’ duties. It remains unclear which agency was responsible for securing that building.

Law enforcement became aware of Crooks after people alerted security that a man was acting strangely outside the rally venue. Attendees saw Crooks pacing near magnetometers at the event entrance, according to reporting from the Associated Press.

The tip sparked a search for Crooks, who was able to elude security and climbed onto the roof.

In multiple videos from the rally and shared on social media, attendees can be heard shouting, “He’s got a gun!” as they point to the nondescript rooftop where Crooks was positioned.

When local police were alerted to the armed man lying on the roof, officers tried to climb up but were deterred when the gunman pointed his weapon at them, sending them ducking for cover, Butler County Sheriff Michael Slupe told local news stations.

Although While the gunman was visible to those at the back of the building, the angle of the roof meant it was far harder for Secret Service snipers to see him until he aimed over the peak with his gun.

Rally attendee and Butler resident David Bocci was seated about 50 to 60 yards away from Trump’s stage on Saturday.

He said he watched as armed Secret Service snipers atop the building behind Trump looked around with binoculars. About three minutes later, he heard what he thought were fireworks. When the noises kept going, he realized they were gunshots. He said he heard the Secret Service yell, “President down!” and panic broke out.

Bocci dropped to the ground with the rest of the crowd before seeing Trump get back up and raise a fist in the air a few moments later.

“It was mind-blowing to me that [Secret Service] were looking and aiming that way for so long and somehow the shooter still got shots off first,” he said.

Police snipers return fire after shots rang out during former President Trump’s campaign rally in Butler, Pa., on July 13, 2024.

(Gene J. Puskar / Associated Press)

Mayorkas did not speak about any specific flaws in Saturday’s security detail.

He declined to say how security has changed for the Trump campaign and for President Biden’s administration. But the direction of the Biden administration, the Secret Service will now also provide a security detail to independent presidential candidate Robert F. Kennedy Jr.

“The Secret Service enhanced former President Trump’s protection based on the evolving nature of threats to the former president and his imminent shift from presumptive nominee to nominee. This includes enhancements related to securing the former president during the Republican National Convention,” Mayorkas said during Monday’s news briefing.

Details of those enhancements would not be made public because they involve sensitive tactics and procedures, he said.

Troy Douthett with the Butler City Council dismissed as “hogwash” the Secret Service’s claim that the shooter was outside its security perimeter.

“Anything in sight should be under their watch,” said Douthett, an independent who voted for Trump in 2016 but did not vote in 2020.

“Local law enforcement is not equipped for protecting a president. That’s just insanity to me. We would have full expectation that the professionals would be professional,” he added.

On Monday, the FBI gained access to Crook’s cellphone, searched his car and home and conducted nearly 100 interviews of “law enforcement personnel, event attendees and other witnesses,” according to a news release from the agency.

The bureau has also received “hundreds of digital media tips” from the public, including images and videos from the scene. Anyone with information can contact the FBI at tips.fbi.gov or (800) 225-5324.

Times staff writers Goldberg and Lin reported from Pennsylvania, Solis and Winton from Los Angeles.