The breaking news was announced by US President Donald Trump on a morning television show.
“I think with a high degree of certainty, we have him,” said Trump on the sofa of Fox & Friends on Friday morning in New York City. “In custody.”
“Essentially, someone that was very close to him turned him in.”
“Somebody is going to say whether it’s a parent or whatever – I’d rather not say right now – somebody that was very close to him said, ‘that’s him,'” Trump added.
It was Trump, too, who first announced that his ally, Kirk, had died after he was shot in the neck at Utah Valley University on Wednesday.
The BBC’s US partner CBS reports a law enforcement source is identifying the person in custody as 22-year-old Tyler Robinson.
The arrest came less than a day after the FBI released grainy pictures of a “person of interest” wanted for the shooting.
Investigators appealed for the public’s help identifying the suspect, who was wearing sunglasses, Converse shoes and a “distinctive” long-sleeved black top featuring an American flag and an eagle.
At a press conference on Thursday night, Utah Governor Spencer Cox had also released a video of what police believed was the suspect fleeing the scene.
The FBI earlier that day said they had found a high-powered firearm – an imported Mauser .30-06 bolt action rifle – wrapped in a towel in a wooded area.
