LATEST: Latest on the Trump rally shooting in Butler County

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BUTLER COUNTY, Pa. — Former President Donald Trump was injured in an assassination attempt shortly after he began speaking at his campaign rally in Butler on Saturday.

One attendee, a former fire chief, was killed and two others were injured. The alleged gunman, identified as Thomas Matthew Crooks, 20, was also killed.

It is the first assassination attempt made on a sitting president or presidential candidate since 1981.

>>> Local officer encountered gunman just before he shot toward Trump at rally, sources tell AP

>>> Butler Trump rally attendees describe panic as shots rang out during attempted Trump assassination

We continue our coverage of this developing story. Stay with Channel 11 and WPXI.com for the latest updates:

Update 11 p.m. Monday:

A pair of sisters who spotted the gunman on a roof moments before the shots rang out said they thought it was a member of the Secret Service doing their job.

Update 10:53 p.m. Monday:

Click here for photos of Trump’s appearance at the RNC.

Update 10:22 p.m. Monday:

Former President Donald Trump has made his first appearance since he was shot in an assassination attempt in Butler County.

Update 9:16 p.m. Monday:

The suspected gunman at former President Donald Trump’s campaign rally in Butler County got onto the roof of the American Glass Research building just outside the Butler Farm Show.

The building is less than 150 yards from the stage where Trump spoke Saturday night.

Channel 11 Chief Investigative Reporter Rick Earle spoke with former Secret Service agent John Hudson, who served three presidents and now lives in the Pittsburgh area. He says it never should have happened.

Update 8:24 p.m. Monday:

Channel 11 is learning more about the men who survived the shooting at former President Donald Trump’s campaign rally in Butler on Saturday.

One of the two attendees who survived is a Marine veteran from New Kensington.

David Dutch, 57, is the Marine Commandant at the American Legion Post 868 in Lower Burrell.

The other survivor was identified as Jim Copenhaver, 74, from Moon Township. He was shot twice at the rally and has a long road to recovery.

Click here to read more about the victims.

Update 7:10 p.m. Monday:

Channel 11 News uncovered dramatic new details Monday in the moments leading up to the assassination attempt on former president Donald Trump. According to multiple law enforcement sources, Thomas Crooks was spotted by law enforcement on a roof nearly 30 minutes before shots were fired that injured Trump, killed a former fire chief and injured two others in the crowd.

Channel 11′s Nicole Ford confirmed that Beaver County’s ESU team had eight members at the rally, including snipers and spotters. According to Ford’s sources, one of them noticed a suspicious man on a roof near the rally at 5:45 p.m., called it in and took a picture of the person. We have learned from our sources the person in that picture is Thomas Crooks. We’re told it’s not clear if Crooks had a gun with him at that point.

Click here to read more.

Update 4:17 p.m. Monday:

The FBI released the following statement Monday about the attempted assassination of Donald Trump:

“The FBI continues to investigate the shooting incident at the July 13 rally in Butler, Pennsylvania, as an assassination attempt on former President Donald Trump and as potential domestic terrorism. The investigation is still in the early stages and the FBI is providing the following updates:

FBI technical specialists successfully gained access to Thomas Matthew Crooks’ phone, and they continue to analyze his electronic devices.

The search of the subject’s residence and vehicle are complete.

The FBI has conducted nearly 100 interviews of law enforcement personnel, event attendees, and other witnesses. That work continues.

The FBI has received hundreds of digital media tips which include photos and videos taken at the scene and we continue to review incoming tips. We encourage anyone with information that may assist with the ongoing investigation to continue to submit it online at tips.fbi.gov or call 1-800-CALL-FBI.

While the investigative work continues, FBI victim services personnel have offered assistance to the victims of Saturday’s incident.

Previous official statements about this incident can be found at https://www.fbi.gov/news/press-releases/fbi-statement-on-incident-in-butler-pennsylvania

Update 2 p.m. Monday:

Neighbors who live next to the Crooks family home tell Channel 11′s Cara Sapida they were evacuated for 24 hours after the attempted assassination. FBI agents told them a “device” needed to be safely removed from the Crooks home.

A former classmate of Thomas Crooks said he was extremely quiet and kept to himself. He said he didn’t ever see him bullied, but felt he was just a quiet kid.

I’m told Thomas often walked around the neighborhood. And a neighbor told me until recently, there were pro-Trump signs in the front yard.

UPDATE 12:50 p.m. Monday:

According to NBC News, Biden spoke with the FBI family liaison for Corey Comperatore, a former fire chief for Buffalo Township who was killed at the rally.

A White House official said Biden made sure his relatives know he is available to speak if a conversation would be “right for them.”

“He was a father. He was protecting his family from the bullets that were being fired and he lost his life, God love him,” Biden said Sunday afternoon.

UPDATE 10:30 a.m. Monday:

The investigation into the alleged gunman, Crooks, continued overnight into this morning in Bethel Park.

Our crews at the scene saw authorities enter Crook’s home around 10 a.m., and then continue to canvas the entire neighborhood.

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UPDATE 9:36 a.m. Monday:

The head of the Secret Service said the agency will “participate fully” in the independent review of the assassination attempt on Trump. The review of how it was allowed to happen was ordered by President Joe Biden.

Director Kimberly Cheatle said on Monday that in addition to the review, the Secret Service will also work with Congress on “any oversight action,” CNN reported.

Cheatle released a statement on Monday saying, “Secret Service personnel on the ground moved quickly during the incident, with our counter sniper team neutralizing the shooter and our agents implementing protective measures to ensure the safety of former president Donald Trump.”

CNN also reported that the Secret Service did not sweep the building where the shooter was located. The agency had local law enforcement conduct security at the business.

UPDATE 9:30 a.m. Monday:

Two days after the attempted assassination of former President Donald Trump, the Republican National Convention is set to begin.

Trump arrived in Milwaukee on Sunday evening for the convention, according to the Associated Press. He told the Washington Examiner that he had rewritten his speech for the event to focus more on national unity than on the policies of President Biden.

As for security, the Secret Service said there are no plans to change what is already in place. Security planning in Milwaukee has been underway for 18 months and has been designated an event that gets the highest level of security.

Michael Hensle, the FBI’s special agent in charge in Milwaukee, told NBC News that “no known specific articulated threat to the RNC during or any specific individual attendee” but that there are higher levels of online “chatter” about the assassination attempt.

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