How one Idaho murder victim likely interrupted, distracted Bryan Kohberger: Police

One of the four University of Idaho murder victims, Xana Kernodle, likely interrupted her killer, Bryan Kohberger, as he was attacking the first two students, according to the lead investigator.

When Kohberger broke into the college students’ home in the early hours of Nov. 13, 2022, he first stabbed best friends Maddie Mogen and Kaylee Goncalves, who were in Mogen’s bed on the third floor, authorities said.

“He chose to go in and kill someone — one right away became two, because they were in bed together,” Idaho State Police Lt. Darren Gilbertson told ABC News.

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Kernodle had just grabbed her DoorDash delivery and was eating in the kitchen on the second floor when she likely heard that commotion, Gilbertson said.

Investigators believe Kernodle went up the stairs toward Mogen’s room, which could’ve distracted Kohberger, Gilbertson said.

When Kernodle interrupted the attack in Mogen’s room, Kohberger may have been “thrown off” and felt “like he has to do something,” Gilbertson said.

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Kohberger left Mogen’s room to follow Kernodle downstairs, Gilbertson said, and in that moment, Kohberger left the knife sheath containing his DNA behind — which helped lead to his capture nearly seven weeks later.

Investigators believe Kohberger didn’t panic and run after Kerndole, but instead walked down the stairs, Gilbertson said. Investigators think this is when Kohberger said, “It’s OK, I’m here to help you” — a phrase one of the two surviving roommates said she overheard from a male voice in the house, according to court documents.

Kohberger likely moved systematically, Gilbertson said, noting that a beer pong table near the stairs wasn’t disturbed.

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Gilbertson said investigators believe Kernodle uttered the words, “somebody’s here,” which was overheard by a surviving roommate on the first floor, according to court documents.

“When Xana made it to her doorway” on the second floor, Gilbertson said, “Kohberger begins to stab her.”

Kernodle was in an “intense struggle” for her life and suffered over 50 stab wounds, a police report said. Kernodle’s boyfriend, Ethan Chapin, who was in her bed, was also fatally stabbed.

Kaylee Goncalves’ sister, Alivea Goncalves, called Kernodle a “hero,” telling ABC News the 20-year-old’s actions showed “savage bravery … to say, ‘Something’s not right, and I’m gonna go see, I’m gonna go help.'”

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Last month, Kohberger was given four life sentences plus 10 years after pleading guilty to all charges in the murders of Kaylee Goncalves, Maddie Mogen, Xana Kernodle and Ethan Chapin. Authorities say a motive is not known and Kohberger declined to speak on his own behalf at sentencing.

According to Gilbertson, Kohberger, a criminology Ph.D. student at Washington State University at the time of the killings, had conversations with peers and co-workers in which he would ask probing questions like, “How would you kill someone?” Investigators believe the crime could’ve been Kohberger’s way of testing out his thesis, Gilbertson said.

Moscow police said they don’t know which victim was the specific target and have not found any link between Kohberger and the victims. But investigators did find Kohberger had multiple pictures saved from social media of female WSU students, Gilbertson said.

ABC News’ Jenna Harrison contributed to this report.