A 22-year-old from Utah has been arrested over the killing of right-wing activist Charlie Kirk, who was shot dead while on stage at a university event earlier this week.

Tyler Robinson was taken into custody late on Thursday after a 33-hour manhunt that ended after his father helped persuade him to surrender to police.

His arrest was first announced by President Donald Trump, who called for the suspect to face the death penalty.

The killing of Kirk, who was shot while debating students on Wednesday, has shocked Americans and laid bare the country's sharp partisan political divisions.

At a news conference on Friday, investigators said the suspect confessed to his father and said he would rather take his own life than surrender. The father then called a youth pastor who is a family friend.

Both men tried to calm the suspect down, police said. The pastor, who also serves as a court security officer, later called the US Marshals who detained the suspect at around 22:00 local time on Thursday.

Utah Governor Spencer Cox said surveillance images showed Robinson arriving on the campus of Utah Valley University around four hours before a shot rang out, killing Kirk and sending students running for cover.

The governor told journalists that when he was taken into custody, he was wearing clothing similar to what was seen on CCTV cameras at the scene of the shooting.

Cox said the family member had spoken of a recent incident when Robinson had mentioned that Kirk was coming to Utah and that he was full of hate and spreading hate. Robinson had reportedly become more politically engaged over recent years.

Cox said investigators had also spoken to a roommate of the suspect who showed them messages about retrieving a rifle from a drop point, suggesting premeditation.

The FBI located the suspected weapon, a Mauser .30-06 bolt-action rifle, wrapped in a towel near the campus.

Inscriptions found on the casings from the scene included messages that indicate a politically charged motive, reflecting the intense divisions within the country.

Students at Utah Valley University expressed relief at the arrest, noting their concerns about safety on campus during such politically contentious times.

Robinson, who is a third-year student at Dixie Technical College, is expected to face several charges including aggravated murder, with formal proceedings anticipated early next week.