The suspected assassin of Charlie Kirk was a “very normal young man” who later developed a “leftist ideology” after appearing to become increasingly radicalized in recent years, Utah Gov. Spencer Cox said Sunday.

Cox revealed the new details about 22-year-old suspect Tyler Robinson to NBC’s “Meet the Press,” though said that investigators are not yet ready to discuss a potential motive as they continue to piece together information about the alleged assassin.

Cox said family and friends of Robinson described his politics as appearing to shift left after dropping out of Utah State University.

“It seemed to happen kind of after that – after he moved back to the southern part of Utah,” he said. “Clearly, there was a lot of gaming going on, friends that have confirmed that there was kind of that deep, dark internet, Reddit culture and these other dark places of the internet where this person was going deep.”

Senior-level FBI officials previously confirmed to Fox News Digital that Robinson was in a “romantic relationship” with a transgender partner. The officials said Robinson lived with the unnamed person, who is a male transitioning to a female and that they shared an apartment in Saint George, Utah.

Tyler Robinson in 2021 in front of the Richard and Moonyeen Anderson Engineering Building (ENGR) at Utah State University. (Amber Robinson via Facebook)

Cox said that the partner has been “very cooperative with authorities.”

Robinson, however, has not been cooperating with authorities since his arrest, according to Cox.

“He has not confessed to authorities. He is not cooperating, but all the people around him are cooperating. And I think that’s, that’s, that’s very important,” Cox told ABC News.

A memorial for Turning Point USA CEO and co-founder Charlie Kirk is seen at Utah Valley University, Saturday, Sept. 13, 2025, in Orem, Utah.  (AP Photo/Lindsey Wasson)

Authorities said Sunday that Robinson is being held under “special watch” pending the completion of a mental health evaluation.

Until Robinson clears a mental health evaluation, authorities are keeping a “close eye” on him, the Utah County Sheriff’s Department said in a statement.

Fox News Digital’s Brooke Singman contributed to this report.