Il Messaggiere - Manhunt underway for shooter who killed Trump ally Charlie Kirk

President Donald Trump lashed out at the "radical left" after the shooting of Kirk, a powerful voice in conservative US politics at just 31 years old, and vowed to crack down on those responsible for what he described as "a dark moment for America."

"For years those on the radical left have compared wonderful Americans like Charlie to Nazis and the world's worst mass murderers and criminals," a somber-looking Trump said in a video message from the Oval Office just hours after Kirk's death.

"This kind of rhetoric is directly responsible for the terrorism that we're seeing in our country today.

"My administration will find each and every one of those who contributed to this atrocity, and to other political violence, including the organizations that fund it and support it."

Kirk was shot in the neck while speaking at an event at Utah Valley University on Wednesday. Video from the scene showed him addressing a large crowd when the sound of a single shot rang out.

The father-of-two appeared to collapse in his chair before the camera swiftly moved and sounds of panic erupted in the audience.

The Utah Department of Public Safety said the shooter, dressed in dark clothing, fired from a nearby rooftop in what authorities called a "targeted attack."

Students at the university described the shooting as "crazy" and "scary".

"It makes me feel like I should be very careful about expressing my political ideas," said Samuel Kimball, a software engineering student, told AFP.

"If I was someone considering going into politics, I’d be afraid to get shot."

- Confusion -

The shooter remained at large despite door-to-door searches by federal, state and local officers.

Orem city mayor David Young said multiple law enforcement agencies were investigating but confirmed that the suspect had not yet been apprehended.

The FBI established a digital line for the public to share tips.

There was initial confusion over the manhunt, with FBI Director Kash Patel posting on social media platform X that the "subject" had been detained before walking that back an hour later.

Trump ordered flags on government buildings -- including the White House -- to be lowered to half-staff until Sunday in an illustration of how important Kirk was in the 79-year-old Republican's orbit.

Utah Governor Spencer Cox, a Republican, called the killing a "political assassination" and issued a stark warning to the perpetrator during an emotional news conference.

"I want to make it crystal clear right now to whoever did this: we will find you, we will try you, and we will hold you accountable to the furthest extent of the law," Cox said.

"And I just want to remind people that we still have the death penalty here in the state of Utah."

- 'He fell back' -

Former Utah congressman Jason Chaffetz, who was at the rally, told Fox News the shooting had happened while Kirk was doing a question-and-answer session with the crowd.

"First question was about religion. He went on for about 15-20 minutes. Second question, interestingly, was about transgender shooters, mass shooters, and in the midst of that, the shot rang out," a visibly shaken Chaffetz told the network.

"As soon as that shot went out, he fell back," he said. "Everybody hit the deck... a lot of people started screaming, and then everybody started running."

- Turning Point -

Kirk had an outsized influence in US politics, powering Trump's support among younger voters -- a key factor in the Republican's return to power last year.

He co-founded Turning Point USA in 2012 to drive conservative viewpoints among young people, his natural showmanship turning him into a go-to spokesman on television networks.

Kirk used his enormous audiences on Instagram and YouTube to build support for anti-immigration policies, outspoken Christianity and gun ownership, and to spread carefully edited clips of his interactions during debates at his many college events.

News of the shooting provoked horror across the political spectrum.

"Eternal rest grant unto him, O Lord," Vice President JD Vance posted on social media.

Figures on the left also condemned the attack and urged calm.

"There is no place in our country for this kind of violence. It must end now," former president Joe Biden wrote on X.

California Governor Gavin Newsom -- a frequent foil for right-wing figures like Kirk -- called the attack "disgusting, vile, and reprehensible."

Former congresswoman Gabrielle Giffords -- a Democrat who herself survived an assassination attempt -- said she was "horrified" by the attack.

Kirk's killing came three months after a Minnesota man shot dead a Democratic lawmaker and her husband in their home.

N.Baggi--IM