A manhunt is underway in Utah for the gunman who fatally shot Turning Point USA co-founder Charlie Kirk, a prominent conservative activist who was making an appearance on a college campus when he was killed.

The identity of the shooter and what motivated the gunman to carry out the assassination is still unknown. The FBI on Sept. 11 released surveillance images of a "person of interest," showing a person wearing a black shirt, jeans, a baseball cap and sunglasses. The bureau asked for the public's help in identifying the person captured on camera.

At a news conference, officials said they recovered a bolt-action rifle used in the shooting and tracked the suspect's movements before and after the incident. The shooter remains at large and appears to be of "college age," said Utah Department of Public Safety Commissioner Beau Mason.

"We are investing everything we have to this and we will catch this individual," Mason said.

Kirk, 31, was among the country's most prominent youth political activists and was a close ally of President Donald Trump and Vice President JD Vance. He made a name for himself as a talented and sometime provocative orator, drawing large crowds at college campuses where he hosted "Prove Me Wrong" debates. Kirk played a key role in Trump's growing popularity among young conservative voters.

The FBI said it's working alongside local and state law enforcement in Utah, and requested that people with information, photos or videos of the incident share them through an online tip page.

"Our investigation continues and we will continue to release information in interest of transparency," FBI Director Kash Patel said on X.

Shooter jumped off rooftop and fled into neighborhood: Officials

Mason told reporters that the shooter arrived near the campus at 11:52 a.m. local time before moving through stairwells and on to a rooftop, where the attacker moved into a "shooting location."

After the shooting, the suspect ran to the other side of the building, jumped to the ground and fled off campus and into a nearby neighborhood. Investigators spoke with neighbors and witnesses and obtained high quality footage of the suspect.

Mason said if law enforcement's initial attempts to identify the shooter are unsuccessful, officials will release images of the suspect to the public.

While authorities have not identified the shooter, Mason said the attacker "appears to be of college age." He added that the "suspect blended in well with the college institution."

Authorities obtain rifle, footprint after Kirk shooting: FBI

Investigators hunting the shooter located a "high-powered bolt action rifle" in a wooded area where the shooter fled, among other pieces of evidence, said Robert Bohls, special agent in charge of the FBI’s Salt Lake City field office.

Bohls said the FBI laboratory will be analyzing the weapon as well as a "footwear impression," a "palm print" and a "forearm imprint" that investigators also discovered.

The bureau has received more than 130 tips since the shooting occurred, Bohls said, adding that the agency will thoroughly investigate every lead.

What happened to Charlie Kirk?

Kirk was sitting under a tent and speaking to a crowd of over 3,000 people, including many college students, when he was shot.

Videos circulating online showed the gruesome scene as Kirk slumped over, and people ducked to the ground before running away and huddling in nearby buildings.

Officials said the gunman was positioned on a rooftop over 100 yards from where Kirk was seated with a microphone.

The event in Orem, Utah, was the latest stop on Kirk's fall campus tour, The American Comeback Tour. During such events, Kirk debates students and others about myriad of topics, some of them controversial. Just before the shot was fired, Kirk and another speaker were discussing school shooters who identify as transgender.

Contributing: Reuters

This article originally appeared on USA TODAY: Suspect in Charlie Kirk shooting still at large. Here's what we know

Reporting by Christopher Cann and Francesca Chambers, USA TODAY / USA TODAY

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