Federal investigators have confirmed that Tyler Robinson, the 22-year-old accused of assassinating Turning Point USA founder Charlie Kirk, was living with his transgender partner in St. George, Utah, at the time of the killing, according to senior-level FBI officials who spoke to Fox News Digital.

Officials described Robinson’s partner, identified in public records as 22-year-old Lance Twiggs, as being in a “romantic relationship” with the suspect and said the two shared an apartment near Robinson’s parents’ home in southern Utah.

The FBI said Twiggs has been “extremely cooperative” with investigators and is not accused of any criminal activity in connection with the assassination. Computers and other evidence were collected from the residence and sent to Quantico for forensic review, Fox News reported.

One FBI official told the outlet that Twiggs “had no idea” Robinson was allegedly planning to kill Kirk. The individual is not facing charges, but authorities emphasized that “every connection, every group, every link will be investigated and anyone involved in this matter, anywhere in the world they might be, will be brought to justice.”

According to a law enforcement source, Robinson’s father recognized his son in surveillance footage that FBI Director Kash Patel had ordered released during the 33-hour manhunt. After conferring with a family minister, Robinson’s father turned him in. The source said Robinson expressed suicidal thoughts when he arrived home, telling relatives he wanted to kill himself.

Authorities say Robinson used a bolt-action rifle to fire a single round from the roof of a building roughly 200 yards away from Utah Valley University in Orem, where Kirk was speaking Wednesday as part of his “American Comeback Tour.” The bullet struck Kirk in the neck, killing him instantly.

Kirk, 31, was a married father of two young children. His death shocked Washington and the conservative movement nationwide, drawing bipartisan condemnation from lawmakers who called the assassination an attack on free speech and democracy.

Utah Gov. Spencer Cox confirmed Friday that investigators found anti-fascist inscriptions on shell casings recovered near the rifle. One casing had been fired, and three others were live rounds. The inscriptions had first been flagged in a bulletin attributed to the Bureau of Alcohol, Tobacco, Firearms and Explosives and circulated on social media before Cox confirmed their authenticity.

A law enforcement source told Axios that Robinson may have been motivated by Kirk’s religious objections to transgender ideology. Six sources familiar with the investigation told the outlet that authorities believe Robinson viewed Kirk’s comments as “hateful” toward Twiggs, which could prove central to establishing motive.

Twiggs was described as “aghast” when informed of the killing and quickly turned over electronic messages Robinson had sent before and after the shooting. In one message, Robinson allegedly wrote that he had discarded the rifle in a wooded area near the university campus and that it would need to be retrieved.

Public records show Twiggs resided at the same St. George address as Robinson. Neighbors told the New York Post they had seen the two men together frequently, including instances where they were observed holding hands and kissing. Another neighbor claimed to have noticed out-of-state cars visiting the property in recent weeks, saying the visitors “did not give off a good vibe.”

Investigators are also examining whether Robinson had ties to local left-wing groups. According to Axios, at least one group in Utah deleted its social media presence immediately after the shooting, drawing additional scrutiny from federal and state authorities.

Kirk’s final moments came just after a tense exchange with a student in the audience. Moments before the shot was fired, he had been asked: “Do you know how many transgender Americans have been mass shooters over the last 10 years?” Kirk replied: “Too many.”

He was then asked about the total number of mass shooters in the U.S., to which he responded: “Counting or not counting gang violence?” Seconds later, the fatal shot rang out.