Federal investigators on Thursday released images of a “person of interest” in the assassination of conservative activist Charlie Kirk, as the hunt continues for the gunman who shot him dead during a campus event in Utah.

Kirk, 31, was delivering a speech to students at Utah Valley University in Orem on Tuesday when a single rifle round struck him in the neck, killing him instantly. Authorities believe the fatal shot was fired from a rooftop about 200 yards away.

The FBI said the newly released images show an individual they want to question in connection with the shooting. Officials stressed the person has not been formally identified as the suspect but urged the public to provide any information that could assist in tracking him down.

READ ALSO: CHARLIE KIRK: FBI HUNTS FOR GUNMAN AFTER ASSASSINATION IN UTAH

The killer remains at large, though investigators say they have pieced together significant evidence of his movements. Surveillance video shows a young man  described as appearing to be of college age  entering a campus stairwell, climbing to the roof, and then fleeing into a nearby neighbourhood after the attack.

A high-powered bolt-action rifle, believed to be the weapon used, was later discovered in a wooded area close to the university. Forensic teams are analysing several clues found at the site, including a footwear impression, a palm print, and a forearm imprint.

“This investigation is moving swiftly,” an FBI spokesperson said. “We are following strong leads and pursuing every avenue to ensure the perpetrator is identified and brought to justice.”

Two individuals detained in the immediate aftermath of the shooting have since been cleared of involvement. Authorities have not yet released the surveillance video itself, citing the sensitivity of the ongoing investigation.

Kirk, who founded the conservative youth organisation, Turning Point USA at age 18, was a prominent ally of former President Donald Trump. In tribute, Trump announced he would award Kirk the Presidential Medal of Freedom posthumously, calling him “a fearless voice for American values.”

The killing has drawn condemnation across the political spectrum and heightened concerns about rising political violence. Vigils have been held nationwide as investigators close in on their lead.

For now, the FBI is urging the public to study the images and come forward with any information.