OREM, Utah (AP) — The man accused in the Charlie Kirk assassination had earlier expressed to family his opposition to the viewpoints of the conservative activist, the authorities said Friday in announcing an arrest in a targeted killing that raised fresh alarms about political violence in the United States.

Tyler Robinson, 22, had become “more political” in the run-up to the shooting and had indicated to a family friend afterwards that he was responsible, said Utah Gov. Spencer Cox. He also cited as key pieces of evidence engravings on bullets found in a rifle believed to have been used in the attack, as well as chatting app messages attributed to the accused shooter that a roommate shared with law enforcement after the shooting.

Cox said some people have asked why there have been so many resources dedicated to investigating Kirk’s killing when there’s violence around the country, but the governor said it is “much bigger than an attack on an individual. It is an attack on all of us.”

The Republican said Kirk’s killing is “an attack on the American experiment” and values, and “cuts to the very foundation of who we are.” He also urged a new generation to “choose a different path.”

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

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

The first FBI agents arrived on the scene at Utah Valley University some 16 minutes after Kirk was shot on Wednesday, FBI Director Kash Patel said at a news conference.

The bureau released the first photos of the suspect on Thursday morning, followed by the announcement of a cash reward and then the release of a video of the suspect climbing down from the roof of a campus building and running away.

“Just last night, the suspect was taken into custody at 10 p.m. local time,” Patel announced.

Robinson’s arrest early Friday morning was disclosed by President Donald Trump, who said in a Fox News Channel interview that, “With a high degree of certainty, we have him.”

Calls to the telephone numbers listed for Robinson in public records rang unanswered.

The FBI and the Justice Department did not immediately comment, but a news conference in Utah, where the killing took place on a college campus this week, was planned for later Friday. 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 that 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 Utah’s governor called a political assassination. Kirk co-founded the nonprofit political organization Turning Point USA, based in Arizona. Authorities recovered a high-powered, bolt-action rifle near the scene of the shooting and had said the shooter jumped off a roof and vanished into the nearby woods afterward.

Kirk had been speaking at a debate hosted by Turning Point at Utah Valley University at the time of Wednesday’s shooting. He was taken to a local hospital and was pronounced dead hours later.

“He wanted to help young people, and he didn’t deserve this,” Trump said Friday. “He was really a good person.”

Federal investigators and state officials on Thursday had released photos and a video of the person they believe is responsible. Kirk was shot as he spoke to a crowd gathered in a courtyard at the university in Orem.

More than 7,000 leads and tips had poured in, officials said. Authorities have yet to cite a motive in the killing, the latest act of political violence to convulse the United States.