The alleged shooter in the fatal attack on conservative activist Charlie Kirk was living with a transgender partner, according to a new report.

That individual, who has not been identified by law enforcement, is cooperating with the FBI, according to Fox News’ digital political correspondent and reporter Brooke Singman.

“Charlie Kirk assassin Tyler Robinson lived with his transgender partner, sources tell me,” she wrote in a post on X. “The individual, who is a male transitioning to a female, is fully cooperating with the FBI. Sources tell me the FBI had texts and other communications between Robinson and the individual that helped FBI authorities solidify that Robinson was indeed the shooter.”

The Washington Examiner and other media outlets have cited sources confirming the report.

The suspect, 22-year-old Tyler Robinson, was apprehended by authorities after a 33-hour manhunt. According to a law enforcement source, text messages and other communications between Robinson and his partner were instrumental in leading federal agents to him. 

During a press conference on Friday, federal and state authorities disclosed that a “roommate” cooperating with the investigation shared communications from a contact named “Tyler.” These messages reportedly described bullet casings matching those found at the crime scene and mentioned the “need to retrieve a rifle from a drop point.”

Public records show that Lance Twiggs, 22, lives at the same three-bedroom apartment in Saint George, Utah, as Mr. Robinson. A roommate showed police texts from Mr. Robinson about stashing a gun linked to Wednesday’s shooting, a law enforcement affidavit said. It is unclear if Mr. Twiggs, who aspired to be a professional gamer, is the same person referenced in the reports and he has not been named in the affidavit.

Mr. Robinson is widely reported to have been living with his parents and siblings in a $650,000 home at Washington County, Utah. However he also maintained an apartment about 5 miles from the house, which he shared with the roommate.

Kirk, 31, founder of the conservative group Turning Point USA, was shot during a stop on his “American Comeback” college speaking tour. The attack occurred just moments after an exchange with an audience member about transgender mass shooters.

Attendee Hunter Kozak asked, “Do you know how many transgender Americans have been mass shooters over the last 10 years?”

“Too many,” Kirk said.

Mr. Kozak followed up, saying, “Do you know how many mass shooters there have been in America over the last 10 years?”

“Counting or not counting gang violence?” Kirk asked.

Immediately after this exchange, a single shot was fired, striking Kirk in the neck. He was rushed to a local hospital where he underwent surgery but was pronounced dead a few hours later. The investigation is ongoing as authorities continue to piece together the motive behind the attack.