We now have some more details of the moments leading up to Tyler Robinson's arrest 33 hours after Charlie Kirk was shot in front of thousands at the campus in Orem, Utah.

According to the BBC's US partner CBS, two law enforcement sources explain Robinson's father knew the suspect was his son from the images which had been released by the FBI.

The sources add that Robinson's father urged the 22-year-old to turn himself in after he had confessed. The father reached out to a family friend who contacted the Washington County Sheriff’s Office with the information.

US Marshals then took Robinson into custody and informed the FBI, the sources say.

Matt Spivey
Live editor

"We got him," Utah Governor Spencer Cox said as he announced the suspect in Charlie Kirk's killing had been caught.

After a flurry of updates from officials, here's what you need to know:

The suspect

• His name is Tyler Robinson, a 22-year-old from from south-west Utah
• Officials confirmed he was not a student at Utah Valley University (UVU). After the news conference, Utah State University has confirmed Robinson had briefly studied there in 2021
• Cox said a family member had described how Robinson had become "more political" in recent years and previously told a relative that he disliked Kirk
• Messages were found on bullet casings at the scene, including "Hey fascist! Catch!" and "if you read this you are gay lmao" - the BBC's Mike Wendling says this could give possible clues to his motive
• His mugshot has been released by authorities and he is being held in custody
• Robinson was registered to vote in 2021 as "unaffiliated" with any political party, according to records seen by the BBC

Image source, HANDOUT

How was Robinson caught?

• Authorities said a family member of Robinson told a family friend that he had confessed, or implied, that he killed Kirk. The friend then relayed this information to a sheriff
• Investigators reviewed footage at UVU of Robinson arriving in a Dodge Challenger vehicle at approximately 08:29 local time (15:29 BST) on Wednesday. Charlie Kirk was shot four hours later at 12:23 - here's a full timeline of events
• Investigators interviewed Robinson's roommate, who showed them messages between him and an account with the name "Tyler" on the messaging app Discord. The messages from "Tyler" talked about needing to retrieve a rifle from a drop point
• Robinson was found by authorities and arrested in Washington, Utah, on 12 September. He was wearing clothing consistent to that worn by the suspect in the video footage

We're continuing to monitor developments so stick with us.

Nick Beake
BBC Verify US Correspondent

We are on our way to Washington County in Utah, after FBI and Utah officials named the suspect in the killing of Charlie Kirk - 22-year-old Tyler Robinson.

Utah State Governor, Spencer Cox, said earlier a "family member" helped turn Robinson in.

We'll let you know what we learn in Washington County, so stick with us.

US President Donald Trump has just posted a tribute to Charlie Kirk on his social media platform, Truth Social, after FBI and Utah officials held a news conference on the investigation into the shooting.

"Everybody loved Charlie!", Trump writes alongside a picture of the pair embracing, with US and Israeli flags behind them. The picture contains the words: 'Great Charlie Kirk. R.I.P Shlomo perl."

Vice President JD Vance has also shared a post on social media thanking authorities for finding the suspect.

"In some ways, the investigation is still in the early days. But I do believe we have the shooter in custody," he says.

"We took a big step this morning in getting justice for Charlie, and for his family. Thanks be to God for that," he writes.

Mike Wendling
BBC News

The markings on the bullets described by authorities indicate that the suspect, Tyler Robinson, was steeped in online culture and included references to themes which could be seen as associated with the Antifa, or the anti-fascist, movement.

A fired shell casing was inscribed with “notices bulges OwO what’s this?” - a reference to a “copypasta” - a piece of text that is repeated over and over again, often to troll people online.

Authorities say one unfired casing had the words “Hey fascist! Catch!” and an up, right and three down arrows. The three down arrows alone could be a common symbol used to represent the anti-fascist movement. As a whole, the sequence of arrows could reference a gaming cheat code - although this remains unclear, and authorities have not yet released images of the casings.

A second casing had the lyrics to a song “Bella Ciao” inscribed on it. The song honours WWII-era partisans of the Italian resistance who fought Nazi Germany.

The third unfired casing was inscribed with the words “If you read this, you are gay lmao” - again an apparent reference to online trolling humour.

Antifa is a loose collection of far-left activists who have been active in the US over the last decade, at street protests and other events.

They often oppose Trump's policies and far-right groups.

Update 19 September: This post has been amended to say that the markings described on the bullets could be references to themes associated with the Antifa movement. The previous version said that they included references to the Antifa movement.

Image source, Reuters

During the news conference earlier, FBI director Kash Patel gave a timeline of the events leading up to Tyler Robinson's capture.

In 33 hours investigators made "historic progress", Patel says.

• At 12:23 local time on Wednesday 10 September, Charlie Kirk was shot
• Within 16 minutes, the first agents had arrived and secured the scene at 12:39
• The FBI "immediately launched fixed-wing assets" (aircrafts) to transport special personnel and evidence
• The first set of FBI photos of the suspect was released at 10:00 local time yesterday
• At 10:45 local time yesterday the FBI reward of $100,000 was announced
• Patel arrived at the scene at 17:30
• At 20:00 the governor led a press conference when video and images of the suspect were released
• And at 22:00 last night the suspect was taken into custody

The Utah governor says the suspect, Tyler Robinson, was not a student at Utah Valley University - where the shooting happened.

Spencer Cox adds he does not have any information about whether Robinson had a history mental health illness.

Robinson had for a long time been living with his family in Washington county, in south west Utah, about three hours away from the university, the governor says.

The governor then says he anticipates charging documents will be filed early next week.

The news conference by FBI and Utah officials has concluded, and we'll bring you a recap of the key lines shortly.

Image source, Reuters

A reporter asks Utah Governor Cox how investigators tracked the suspect, Tyler Robinson, down.

We know that Robinson drove, Cox says. His car was on campus then he drove south back to Washington city in Washington County, Utah.

Another journalist asks whether Kirk's death represents a "watershed moment" for the US.

"This is a watershed moment, but we don't yet know what kind," Cox replies.

He says this moment "feels a lot like the late 60s" and describes social media as a "cancer", adding that humans are not "biologically capable of processing... violent imagery".

He encourages people to "log off, turn off, touch grass, hug a family member, go out and do good in your community".

"This our moment. Do we escalate or do we find an off-ramp? It's a choice, and every one of us gets to make that choice," he says.

The news conference by FBI and Utah officials has now concluded, but we'll continue to bring you the key lines from it here.

Taking questions from journalists, the Utah governor is asked whether there is potential for further arrests.

"We do not have information at this time that would lead to additional arrests, but the investigation is ongoing," responds Spencer Cox.

He says Robinson is currently being held at Utah County jail. He was delivered to custody with the help of Robinson's family and a friend, he says.

Utah Governor Spencer Cox is visibly emotional and says in the past 48 hours: "I have been as angry as I have ever been, as sad as I have ever been."

"As anger pushed me to the brink, Charlie's words brought me back," he says.

He quotes Kirk as saying "When people stop talking, that's when you get violence".

He adds that young people "loved and hated Charlie" and he "went into those places anyway".

He then addresses young people and says: "You are inheriting a country where politics feels like rage. It feels like rage is the only option."

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

"There is one person responsible for what happened here and that person is now in custody and will be charged soon and will be held accountable," he adds.

Image source, Getty Images

Utah Governor Spencer Cox returns to the podium and says he wants to address "where we are and how we got here".

He says violence is tragic everywhere and explains Kirk's killing is "much bigger than an attack on an individual".

"It is an attack on all of us. It is an attack on the American experiment, it is an attack on our ideals," he says, adding it "cuts to the very foundation of who we are".

Cox says Kirk being killed while championing freedom of expression makes it "more difficult for people to feel like they can share their ideas" and speak freely.

"We will never be able to solve all the other problems - including the violence problems that people are worried about - if we can't have a clash of ideas safely and securely. Even - especially, especially, those ideas with which you disagree," he adds.

Image source, Reuters

Sheriff Mike Smith is speaking now, who says it has been a "vast, complicated and very, very fast paced investigation".

He says the investigation has "been very taxing" before praising the level of cooperation in this case and thanking the public.

He says the law enforcement community and the Kirk family need prayers and support to get through this time.

"We've had such a phenomenal response to this. Thank you," Smith says, addressing the public.

FBI Director Kash Patel says the crime scene is "large" but has been "processed quickly" and he's been able "to walk through the steps the suspect took".

He says forensic evidence has been seized and has already been evaluated, with thousands of more leads being followed.

"The arrest is a testament to the dedication of good law enforcement being great," Patel adds.

Image source, Reuters

Speaking now is FBI Director Kash Patel, who says he is proud to stand here and bring Kirk's family justice.

He especially thanks Kirk's parents, widow and children - all of whom will be involved in bringing Kirk justice, he says.

Patel also expresses gratitude to President Trump and Vice President JD Vance, who "had our backs the entire way".

"I just want to express my gratitude for giving us the resources we need to operate in this space to bring this sort of justice at this sort of speed. In 33 hours, we have made historic progress for Charlie," he says.

Image source, Getty Images

Governor Cox pays tribute to law enforcement, the FBI and the public for being so engaged and "helping us get to this point".

The Utah governor then thanks the family members of the suspect, Tyler Robinson, who "did the right thing" and brought him to law enforcement.

"I especially want to thank the family of Charlie Kirk," he tells the news conference, adding: "I want us to be thinking of them as we bring justice to this case."

Cox says investigators found a bolt action rifle wrapped in a dark towel and the gun had a scope mount on top of it.

He notes there were inscriptions on bullet casings, including one which read: "Notices bulges owo". There were also inscriptions on three unfired casings, Cox explains.

Cox says some of the inscriptions include: "Hey fascist! Catch!", "O Bella Ciao, Bella Ciao" and "if you read this you are gay lmao".

("Bella ciao" is an Italian song dedicated to the Italian resistance who fought against the occupying troops of Nazi Germany.)

Cox says that investigators interviewed Robinson's roommate, who showed them messages between him and an account with the name "Tyler" on the messaging app Discord.

The messages from "Tyler" stated the need to retrieve a rifle from a drop point and leaving the rifle in a bush. The messages also stated he was watching an area where the rifle was left and how the weapon was wrapped in a towel, Cox says.

He says the messages also mentioned engraving bullets, a scope, and the rifle being "unique".

"Tyler" also mentioned that he had changed outfits in the messages, Cox adds.

Image source, Reuters

We're still hearing from Utah Governor Spencer Cox at the press conference.

Cox continues and says a member of the suspect's family told investigators that Tyler Robinson had become "more political" in recent years.

Cox says the family member recalled a recent incident in which Robinson came to dinner before 10 September and mentioned Charlie Kirk was coming to Utah Valley University, and talked about why he "didn't like him and the viewpoints he had".

Robinson had told a family member that "Kirk was full of hate and spreading hate", according to Cox.

Cox says investigators reviewed video footage, and identified Robinson arriving in a Dodge Challenger vehicle at approximately 08:29 local time on 10 September.

When encountered in person by investigators on 12 September, he was observed in clothing consistent to that in the footage, including a "plain maroon t-shirt, light-coloured shorts, a black hat with a white logo and light-coloured shoes".