Authorities announced the arrest of a 22-year-old Utah man on suspicion of killing conservative activist Charlie Kirk during a Wednesday event at Utah Valley University.

Tyler Robinson was taken into custody on Thursday night, and investigators said they believe he acted alone.

Kirk, the chief executive and co-founder of the conservative youth organisation Turning Point USA, was a top podcaster and ally of President Donald Trump.

He led an effort to remake the Republican Party’s get-out-the-vote effort in the 2024 election.

Here are moments leading up to Kirk’s event, his death and Robinson's arrest. All times are local.

Friday, August 29

Ahead of Kirk's visit to Utah Valley University, a change.org petition is started titled “Prevent Charlie Kirk from speaking at Utah Valley University.”

Wednesday, September 3

Utah Valley University releases a statement affirming its “commitment to free speech, intellectual inquiry, and constructive dialogue.”

Wednesday, September 10

11.52am: The suspected shooter arrives on campus, according to Beau Mason, the commissioner of the Utah Department of Public Safety, who spoke at a Wednesday news conference following Kirk's death.

Noon: Kirk kicks off his event in the Fountain Courtyard of Utah Valley University's Orem Campus.

About 12.20pm: As the “debate” portion of Kirk's event began, one gunshot rang out, Utah Valley University spokeswoman Ellen Treanor told the AP.

Authorities believe the gunshot came from the Losee Centre, about 183 metres away from where Kirk was speaking.

12.23pm: A Utah Valley University police officer states, “Alpha 34, we have shots fired. Charlie Kirk is down”, according to a broadcast recording from the department's dispatch line made available by OpenMHz.

Shortly after, a different officer notes that there was gunfire and that Kirk is"on his way to the ambulance. He’s on his way to the hospital".

12.39pm: FBI agents arrive on the scene at Utah Valley University, according to FBI Director Kash Patel.

Around this time, videos begin to appear on social media that show Kirk speaking into a handheld microphone while sitting under a white tent emblazoned with the slogans ”The American Comeback” and ”Prove Me Wrong”.

A single shot rings out, and Kirk can be seen reaching up with his right hand as a large volume of blood gushes from the left side of his neck.

Stunned spectators are heard gasping and screaming before people start to run away.

12.47pm: Utah Valley University issues an alert that says a “single shot” was fired. It also says that the suspect is in custody.

2.45pm: Orem Mayor David Young says the suspected shooter remains at large.

4.21pm: Patel says on social media that “the subject for the horrific shooting today that took the life of Charlie Kirk is now in custody."

4.30pm: During a news conference, authorities confirm Kirk was brought to Timpanogos Regional Hospital and died there. They say no one is in custody and the suspect remains at large.

5.59pm: Patel posts on social media:"The subject in custody has been released after an interrogation by law enforcement. Our investigation continues and we will continue to release information in interest of transparency”

Thursday, September 11

7.55pm: The FBI said it was looking for a “person of interest” and released a series of photos showing the person wearing a hat, sunglasses, a long-sleeve black shirt, and a backpack.

Police released video of the person racing across the roof of the building from where authorities say the shot was fired, dropping down to the ground and walking off campus.

At some point that evening, a family member of Robinson's reached out to a family friend who contacted authorities with information that Robinson had confessed or implied that he carried out the shooting, Utah Governor Spencer Cox said Friday.

10pm: Robinson was taken into custody, officials said Friday.

Friday, September 12

8.05am: Authorities announce that 22-year-old Tyler Robinson from Utah is in custody in Kirk's shooting. Robinson was booked into Utah County Jail.

About 10.20am: A probable cause statement outlines the evidence gathered against Robinson, who was arrested on suspicion of aggravated murder, felony discharge of a weapon causing serious bodily injury, and obstruction of justice.

All are state felony charges, and aggravated murder carries the possibility of the death penalty.

Formal charges are expected early next week.