Retired Army captain at deadly Trump rally reveals 'tactical reason' Secret Service should've been on ARG roof
Sean Parnell was in front row of Saturday's Trump rally in Butler, Pa
{{#rendered}} {{/rendered}}The Secret Service should have foreseen a "tactical reason" to have countersnipers placed on the AGR building rooftop at former President Trump's Pennsylvania rally on Saturday – where gunman Thomas Matthew Crooks opened fire – according to a retired Army infantry captain who witnessed the chaos from the front row.
"I've been in more firefights than I can count, I can tell you, but I've never been in anything like that," Sean Parnell, a former congressional candidate who can be seen in photos of the shooting just steps away from Trump on stage right, told Fox News Digital.
"Doesn’t it make sense to engage behind the president, too?" he added. "There was a tactical reason for that to be occupied."
{{#rendered}} {{/rendered}}THOMAS MATTHEW CROOKS HID RIFLE IN ADVANCE OF TRUMP RALLY SNIPER ATTACK, SECRET SERVICE SOURCE SAYS
President Trump speaks to supporters on July 13, 2024, in Butler, Pa. Sean Parnell, a retired Army captain and former congressional candidate from the area, can be seen near the bottom right. The building in the background is where would-be assassin Thomas Matthew Crooks climbed up and opened fire. (Courtesy of Linda Musulin)
Parnell said that as soon as he arrived at the rally, he took a general look around and potential security vulnerabilities stood out to him, but he also saw a strong police presence.
FORMER SECRET SERVICE AGENT SAYS TRUMP WOULD-BE ASSASSIN THOMAS CROOKS SCOUTED RALLY SPOT IN ADVANCE
{{#rendered}} {{/rendered}}"They're not firecrackers. It's sniper fire. Get down quickly!"
"As a combat veteran, 16 months in Afghanistan, I'll tell you that looking for threats like that is, once you come back from combat, you're kind of wired like that," he said. "That experience that never leaves you. I didn’t think anything was going to go wrong. I'm at a political rally … but you still think about that."
He said his immediate thought was that the gunman was either perched on a nearby water tower or the AGR building to the north of the stage.
"Instantly, it was like building or water tower," he recalled. "But there's no freaking way. The Secret Service would have that on lockdown."
{{#rendered}} {{/rendered}}But somehow, Thomas Matthew Crooks, 20, was able to climb on top of it with a rifle.
EXCLUSIVE TRUMP RALLY VIDEO SHOWS CHAOS AFTER GUNMAN OPENED FIRE
There were four countersniper teams stationed around the rally, according to the Secret Service (USSS): two from the agency and two provided by local law enforcement.
{{#rendered}} {{/rendered}}Of the four teams, two opened fire, one local and from the USSS. A Secret Service sharpshooter fatally struck the gunman seconds after the gunfire erupted.
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Crooks struck at least four people with AR-15 fire from the rooftop, killing a 50-year-old father of two named Corey Comperatore and seriously wounding David Dutch, 57, and James Copenhaver, 74.
{{#rendered}} {{/rendered}}President Trump later said he had been shot in the right ear, and photos from the scene showed him getting back to his feet after ducking for cover with blood on the right side of his head.
Parnell was standing next to his wife in the front row between Crooks and the former president.
{{#rendered}} {{/rendered}}"When those rounds cracked over my head, we were directly in the line of fire," he said. "I knew immediately it was a sniper. I got my wife down … 'They're not firecrackers. It's sniper fire. Get down quickly!'"
Republican presidential candidate Donald Trump gestures to the crowd as Secret Service agents rush him from the stage during an attempted assassination at his campaign rally in Butler, Pa., on July 13, 2024. (AP Photo/Gene J. Puskar)
A source told Fox News on Thursday that Crooks had hidden the murder weapon somewhere ahead of time.
{{#rendered}} {{/rendered}}Authorities also revealed that his final message on the online gaming platform Steam included an ominous claim: "July 13 will be my premiere, watch as it unfolds."
After countersnipers neutralized the threat, medics rushed into the audience to treat the victims.
Parnell had encountered one of them before: Comperatore, a local engineer and volunteer firefighter.
{{#rendered}} {{/rendered}}Parnell, a former Army Ranger who is from the area and has been a congressional candidate, said he once met the father of two on the campaign trail.
"A lot of people that go to those rallies are the very same people that supported me," he said. "It would be an overstatement to say I knew him, but I definitely shook his hand."
{{#rendered}} {{/rendered}}Wake services for Comperatore were scheduled for Thursday. He will be laid to rest Friday after a private ceremony.
Fox News' David Spunt and Ashley Papa contributed to this report.