OREM, Utah – Utah dispatch audio reveals the frantic moments after an unidentified assassin fatally shot conservative speaker and Turning Point USA founder Charlie Kirk on a college campus Wednesday afternoon.

The call came in around 12:20 p.m. — about 20 minutes into Kirk’s “American Comeback Tour” appearance at Utah Valley University, according to school officials. He had been invited to speak by the campus’ chapter of TPUSA.

A dispatcher said a single individual had been shot, and it was “unknown where the shooter went.”

The manhunt remained active Thursday morning. Investigators said Thursday morning that they traced the sniper’s escape route and recovered a “high-powered, bolt-action rifle,” according to FBI Salt Lake City Special Agent in Charge Robert Bohls. He said investigators also obtained foot, palm and forearm imprints linked to the crime.

VIDEO SHOWS MOMENTS BEFORE ASSASSINATION OF TURNING POINT USA FOUNDER CHARLIE KIRK

“Be advised, UVU in Orem has had an active shooter at the Charlie Kirk event,” a dispatcher said over the radio after the shooting, according to audio provided by Broadcastify. “We’re getting several calls. I’m trying to get more information.”

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“They requesting help?” a man’s voice replied.

“We’re not sure yet,” she said. “We’re just trying to get units that way.”

Police were already on scene. So was a private security team hired by Kirk, which helped rush him to the hospital. He was the only reported injury.

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Later, dispatchers discussed a suspect description.

“He’s going to be wearing all black, black long gun, black tactical helmet, a black mask, possibly wearing a tactical vest and jeans,” a female dispatcher said over the radio, according to recordings.

Authorities said the killer arrived around 11:52 a.m. and climbed onto a rooftop through a campus building’s stairwell. The 31-year-old Kirk’s event began at noon. After the shooting, the suspected assassin jumped down the other side of the building and fled into a neighborhood, where police were canvassing for video evidence.

Police initially took a man named George Zinn into custody, charged him with obstruction and released him. A second person of interest, identified as Zachariah Qureshi, was also taken into custody, questioned and released.

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“There are no current ties to the shooting with either of these individuals,” a Utah Department of Public Safety spokeswoman said in a statement. “There is an ongoing investigation and manhunt for the shooter.”

Kirk, a 31-year-old father of two, was sitting under a tent, debating with students on hot-button current affairs issues, when the unidentified killer opened fire.

A single gunshot cracked through the air, according to videos of the event. Witnesses screamed in horror and fled for cover after the bullet struck Kirk in the neck. He was rushed to a hospital and later pronounced dead.

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Other video circulating online appears to show a dark-clad figure on a rooftop. Authorities said the gunshot came from about 200 yards away, likely from a perch atop the Losee Center building, which is on the opposite side of the plaza from where Kirk was speaking.

“It’s going to be basic police work here,” said David Katz, a former DEA special agent and the CEO of Global Security Group. “They should be pulling every cellphone ping from that small geographic area.”

He said Utah investigators would also be looking back at surveillance video for weeks to see if anyone accessed the same rooftop.

“They need to be focused on mechanisms of escape,” he said. “Every single car in the area. I imagine he didn’t get away on public transportation in Utah, so it’s got to be a vehicle. After the shot, it would have taken seconds for him to get down. I don’t know if he discarded the gun, but it would have been a simple matter of changing your shirt and leaving the area quickly.”