(The Hill) — Utah Gov. Spencer Cox (R) stated on Sunday that the alleged assassin in the fatal shooting of conservative activist Charlie Kirk last week was romantically involved with his roommate, who Cox mentioned is cooperating with law enforcement.

Cox also said the roommate is transgender, confirming reporting from Fox News.

“There are a couple things that we can confirm that have been reported,” Cox said in an interview on NBC News’s “Meet the Press.”

“We do know that the roommate that we had originally talked about, we can confirm that that roommate is a boyfriend who is transitioning from male to female,” Cox highlighted. “So we know that piece.”

“I will say that that person has been very cooperative with authorities,” he continued.

Cox said authorities have additional forensic evidence that will be presented when charges are formally filed on Tuesday.

He said the motive for the alleged assassin is not yet clear.

Cox said the suspect “does come from a conservative family,” according to family and friends, “But his ideology was very different than his family.”

The alleged gunman, Tyler Robinson, was apprehended by the FBI late Thursday evening. Law enforcement reported that Robinson, 22, hinted at his involvement in the shooting to a family member, who then informed a family friend, who subsequently notified authorities.

Cox said at a press conference on Friday morning that a family member described Robinson as becoming increasingly political in recent years.

“The family member referenced a recent incident in which Robinson attended dinner before Sept. 10, and during a conversation with another family member, Robinson mentioned that Charlie Kirk was coming to [Utah Valley University,]” Cox stated.

“They discussed why they disliked him and his viewpoints. The family member also remarked that Kirk was full of hate and spreading hate,” Cox added.