The man accused of shooting and killing conservative activist Charlie Kirk last week is not cooperating with authorities, Utah Gov. Spencer Cox said Sunday.

A mural of slain Charlie Kirk, with angel wings and halo, was painted within 24 hours of his death by Dudi Shoval, an Israeli graffiti artist, in the southern Israeli city of Ashdod. Photo by Debbie Hill/ UPI UPI FBI Director Kash Patel (R) speaks to Utah Governor Spencer Cox at a press conference on Friday about the killing of conservative activist Charlie Kirk on the campus of Utah Valley University in Orem, Utah. Photo by Bob Strong/UPI UPI Tyler Robinson, 22, of Utah, is pictured in his mugshot on Friday, September 12, 2025. According to law enforcement, Robinson confessed to his father that he had shot conservative influencer Charlie Kirk on Wednesday during a speaking event at Utah Valley University. UPI

Sept. 14 (UPI) -- The man accused of shooting and killing conservative activist Charlie Kirk last week is not cooperating with authorities, Utah Gov. Spencer Cox said Sunday, as questions of his motivations linger.

Tyler Robinson, 22, was arrested Friday after a family member saw photos of the suspect and turned him in to police.

He has been reported to have come from a Trump-supporting Republican family and is speculated to have possibly been a follower of white nationalist Nick Fuentes, based on messages inscribed on unused ammo left at the crime scene, leaving discussions about his political leanings and motivations ambiguous.

"He has not confessed to authorities. He is not cooperating," Cox said in an interview with ABC News' "This Week" co-anchor Martha Raddatz. "But all the people around him are cooperating. And I think that's very important."

In the interview, Cox was asked about a report from The New York Times that alleged Robinson discussed being the gunman in messages with friends on Discord. Cox revealed that his friends believed he was joking until he allegedly confessed to them.

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A report from the New York Post citing an anonymous source had also revealed that Robinson lived with a boyfriend who is transitioning from male to female, which Cox confirmed.

"It's easy to draw conclusions from that," Cox said while addressing the same topic with CNN on Sunday.

It is not clear whether the alleged gender identity of Robinson's roommate had any bearing on his motivation for Kirk's shooting, and the allegation has enflamed anti-trans rhetoric from Kirk's supporters online. At the time of his death, Kirk was answering a question about transgender people and mass shootings.

Cox said that the roommate is cooperating with authorities.

Cox previously told the Wall Street Journal that Robinson was "deeply indoctrinated with leftist ideology" but when asked by ABC News on Sunday if any evidence could prove that, he said that had come from "his acquaintance and his family members."

Cox pledged that "much more evidence" of leftist ideology would be provided on Tuesday when official charges are expected to be filed.

Meanwhile, Kirk's supporters have led efforts to call for the firing of people who have celebrated his death publicly or did not sufficiently mourn his death.

A website has been set up to track criticism of Kirk, celebrating each confirmed case a person has been fired.

"This website will soon be converted into a searchable database of over 30,000 submissions, filterable by general location and job industry," the website reads. "This is a permanent and continuously-updating archive of Radical activists calling for violence."

Despite the murkiness of Robinson's views and motivations, President Donald Trump and his supporters have threatened retaliation against Democrats in the wake of the shooting.

Rep. Clay Higgins said in a statement after the shooting that he would use congressional authority to ensure that social media platforms ban "ever post or commenter that belittled the assassination of Charlie Kirk" for life.

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"If they ran their mouth with their smartass hatred celebrating the heinous murder ... those profiles must come down," Higgins wrote.

"I'm going to lean forward in this fight, demanding that big tech have zero tolerance for violent political hate content, the user to be banned from all platforms forever. I'm also going after their business licenses and permitting. Their businesses will be blacklisted aggressively, they should be kicked from every school, and their drivers licenses should be revoked."

Deputy Secretary of State Christopher Landau said in a statement after the shooting that the United States government would move to punish any foreigners for "making light" of Kirk's death.

"I have been disgusted to see some on social media praising, rationalizing, or making light of the event, and have directed our consular officials to undertake appropriate action," Landau said. "Please feel free to bring such comments by foreigners to my attention so that the @StateDept can protect the American people."

The reaction from supporters of Kirk stands in contrast to past reactions to other acts of political violence in the United States, including by Kirk himself.

In October 2022, a man broke into House Speaker Nancy Pelosi's San Francisco home and attacked her husband, Paul Pelosi, with a hammer, fracturing his skull and causing serious injuries. Kirk said he thought the attack was "awful" but urged an "amazing patriot" in San Francisco to bail the attacker out of jail.

After that same attack, Higgins posted a photo making fun of it and later deleted the post while Laura Loomer, a prominent Trump ally, falsely suggested that Paul Pelosi and his attacker were lovers.