GEOFF BENNETT: Welcome to the "News Hour."

The man accused of killing conservative activist Charlie Kirk is now in custody.

AMNA NAWAZ: The arrest came after an extensive search.

The FBI had called on the public for help, posting surveillance photos and videos and issuing a $100,000 reward.

As Stephanie Sy reports, it was information from the suspect's own family members that ultimately led to his arrest.

GOV.

SPENCER COX (R-UT): Good morning, ladies and gentlemen.

We got him.

STEPHANIE SY: After a massive manhunt, police have the young man they believe killed Charlie Kirk.

Tyler Robinson is a 22-year-old Utah resident.

The state's governor described how the tip came in.

GOV.

SPENCER COX: A family member of Tyler Robinson reached out to a family friend, who contacted the Washington County Sheriff's Office with information that Robinson had confessed to them or implied that he had committed the incident.

STEPHANIE SY: He was arrested today and is being held on initial charges, including aggravated murder.

Robinson's family members told authorities that he had become more political lately.

GOV.

SPENCER COX: Robinson mentioned Charlie Kirk was coming to UVU.

They talked about why they didn't like him and the viewpoints that he had.

The family member also stated Kirk was full of hate and spreading hate.

STEPHANIE SY: Kirk was shot by a sniper on Wednesday on the campus of Utah Valley University.

A crowd of thousands had gathered for the kickoff of his so-called American Comeback Tour.

Later, the FBI released this surveillance video that they say shows the shooter escaping the crime scene.

They collected evidence from the rooftop.

GOV.

SPENCER COX: Inscriptions on the three unfired casings read, "Hey, fascist!, Catch!"

STEPHANIE SY: Cox said investigators have also discovered messages between Robinson and a roommate that corroborated the details of the weapon and engraved casings.

KASH PATEL, FBI Director: In 33 hours, we have made historic progress for Charlie.

STEPHANIE SY: FBI Director Kash Patel, who early in the search released conflicting information about a possible suspect, said the investigation would continue.

KASH PATEL: This would not have been possible without you the media and you the public.

That's why we went so public so fast and were so transparent.

And we're committed to that transparency.

STEPHANIE SY: After giving the latest on the investigation, Governor Cox addressed the moment in broader terms.

GOV.

SPENCER COX: I don't want to get too preachy, but I think it's important that we, with eyes wide open, understand what's happening in our country today.

STEPHANIE SY: The Republican called out the political nature of the violence, which he has called an assassination.

GOV.

SPENCER COX: It is also much bigger than an attack on an individual.

It is an attack on all of us.

It is an attack on the American experiment.

STEPHANIE SY: He spoke to Kirk's followers and opponents, many of them young people.

GOV.

SPENCER COX: You are inheriting a country where politics feels like rage.

It feels like rage is the only option.

Your generation has an opportunity to build a culture that is very different than what we are suffering through right now, not by pretending differences don't matter, but by embracing our differences and having those hard conversations.

STEPHANIE SY: On FOX News this morning, the president had a different emphasis.

DONALD TRUMP, President of the United States: I hope he gets a death penalty, what he did.

Charlie Kirk was the finest person.

He didn't deserve this.

STEPHANIE SY: While political violence has claimed victims on both sides of the aisle, President Trump today said the left is more to blame.

DONALD TRUMP: I will tell you something that's going to get me in trouble, but I couldn't care less.

The radicals on the right oftentimes are radical because they don't want to see crime.

They don't want to see crime.

The radicals on the left are the problem, and they're vicious and they're horrible.

And they're politically savvy.

STEPHANIE SY: So close was he to the Trump administration that, last night, Charlie Kirk's body was flown from Utah to Arizona on Air Force Two.

Vice President J.D.

Vance accompanied Kirk's widow, Erika, on the trip and described Kirk as a true friend.

Kirk founded the campus activist group Turning Point USA at 18.

His influence is credited with helping Trump win, and he became a close confidant to many in the White House.

While his views earned him a loyal following, they also made him a target.

He was often engaging in debates on college campuses, which is where, last night, students across the country gathered to mourn.

BARRETT RATLIFF, Texas A&M University Student: All we can do is pray and look to the lord for guidance.

And I think this really will be the turning point that Charlie's been preaching and been doing since he started.

LAUREN CAGGIANO, Florida Atlantic University Student: Turning Point next year and even this year is going to be bigger than ever.

We're going to keep his message alive.

STEPHANIE SY: Turning Point USA says it has more than 850 chapters on U.S. campuses.

For the "PBS News Hour," I'm Stephanie Sy.