US President Donald Trump confirmed that he does not fear for his safety in light of the fallout from the killing of American political activist Charlie Kirk in Utah.

When asked on Thursday if he had such concerns, he replied:"No, I'm not very worried."

"We're really concerned about our country," the US president told reporters on the South Lawn of the White House."We have a radical left-wing group of lunatics, absolutely lunatics, and we're going to solve this problem. I'm just concerned about the country."

Kirk, 31, was shot and killed during a gathering at Utah Valley University on Wednesday by a gunman who was caught on camera rushing across the roof of a building moments after opening fire.

Kirk was struck by a single bullet while speaking to a crowd at Orem State University. He collapsed immediately after being hit and was taken to the hospital, where he later died of his injuries.

President Donald Trump announced Kirk's death and posted a moving eulogy on Truth Social, saying,"No one understood or captured the heart of the youth of the United States of America better than Charlie."

A massive manhunt is currently underway by the FBI and Utah police to find the killer.