OREM, Utah () The man suspected of killing Charlie Kirk has been identified as Tyler Robinson, a 22-year-old man from southern Utah, authorities announced Friday.

How was Tyler Robinson caught?

According to authorities, Robinson confessed to a family friend or “implied that he had committed the murder” and that person in turn contacted the Washington County Sheriff’s Office on Thursday. Robinson was arrested at about 10 p.m. local time.

sources said Robinson was on the FBI’s radar Thursday and was initially identified through facial recognition investigative methods.

What we know about the weapon

A high-powered, bolt-action rifle was found wrapped in a towel with inscriptions on the bullet casings, according to Utah Gov. Spencer Cox.

What was on the gun?

Bullet casings discovered by investigators had several inscriptions engraved on them, Cox said. The casing that had been fired read: “notices bulges OWO what’s this?”

The third fired casing read: “if you read this you are gay lmao.”

Cox said there were three unfired casings:

One read, “hey fascist! catch!” with an up arrow symbol, right arrow symbol, and three down arrow symbols.

Another one read: “oh bella ciao bella ciao bella ciao ciao ciao,” Cox said.

What we know about Tyler Robinson

It was not clear Friday what, if any, affiliation the suspect had with Utah Valley University, where the shooting occurred. He was not a student at the university.

His family told investigators he had become “more political” recently and spoke about his dislike for Kirk.

Robinson is believed to have acted alone, and the investigation is ongoing, Cox said.

He’s being held at the Utah County Jail in Spanish Fork, about 11 miles south of Utah Valley University.

Utah State University confirms Robinson attended one semester at the university Logan campus as a pre-engineering major. He took a leave of absence after that lone semester.

News of the arrest came hours after the FBI and state officials had pleaded for public help by releasing additional photographs of the suspect, a move that seemed to indicate law enforcement was uncertain of the person’s whereabouts.

Kirk was killed by a single shot in what police said was a targeted attack and what Cox called a political assassination. Kirk co-founded the nonprofit political organization Turning Point USA, based in Arizona.

This is a developing story. Refresh for updates.