The FBI has released images of a person of interest in the assassination of Charlie Kirk, a prominent MAGA campaigner and conservative commentator, as investigators offer a $US100,000 reward for information leading to the suspect’s arrest.

Kirk, 31, was shot dead while addressing a rally at Utah Valley University in Orem, about 65km south of Salt Lake City. He was struck in the neck by a single bullet just after midday while answering an audience question about mass shootings.

Authorities say the shooter, described as “college-aged”, arrived on campus minutes before the event began and climbed to a rooftop overlooking the outdoor crowd of roughly 3,000 people. Security-camera footage shows the armed individual ascending stairwells before firing at Kirk, FBI officials told reporters.

In newly released images, the person of interest is seen wearing jeans, a long-sleeved black shirt with what appears to be an American flag on the front, black sunglasses, a cap and a backpack.

“We are asking for the public’s help identifying this person of interest in connection with the fatal shooting of Charlie Kirk at Utah Valley University,” the FBI’s Salt Lake City office wrote on X.

The gunman fled the scene by jumping from the rooftop into a nearby neighbourhood, FBI special agent Robert Bohls said. A high-powered bolt-action rifle believed to have been used in the killing was later discovered in a wooded area close to the campus, along with palm prints and footprints.

On Thursday, the campus remained closed as investigators combed through evidence, with yellow tape sealing off rooftops and wooded areas. Utah Public Safety Commissioner Beau Mason said the shooter had “blended in well” with the university crowd before the attack.

The Wall Street Journal reported that engravings related to transgender and anti-fascist ideology may have been found on ammunition linked to the gunman, though sources familiar with the investigation cautioned it was too early to confirm any motive.

In Washington, President Donald Trump announced Kirk would be posthumously awarded the Presidential Medal of Freedom, the nation’s highest civilian honour, for his contributions to political activism and public debate.

“The FBI is offering a reward of up to $US100,000 for information leading to the identification and arrest of the individual(s) responsible for the murder of Charlie Kirk,” the bureau said.

Anyone with information is urged to contact the Salt Lake City FBI office.

Images: FBI Salt Lake City