The man suspected of slaughtering four University of Idaho students reportedly kept a low profile at his Washington State University apartment complex with some neighbors not even realizing the accused killer lived among them.

Bryan Kohberger, 28, who was charged with four counts of first-degree murder, returned to college following the slayings and finished off his first semester as a doctoral student studying criminal justice, the school confirmed in a statement.

Justin Williams, a 34-year-old employee at WSU who lives in an adjacent building to Kohberger, told Fox News Digital that he rarely saw the alleged murderer.

“I’d see him go check his mail, that was it. Other than that, I’ve only seen him like twice the whole time, and I’ve lived here since July 2021,” Williams said, who added he noted “nothing unusual” in Kohberger’s behavior.

Neighbors told the news outlet the Steptoe Village building is part of a WSU housing complex, which is mostly inhabited by graduate or PhD students and is a “quiet” area in the typically safe city of Pullman — about a 15-minute drive across the Idaho border to Moscow, where the four students were slain.

Andrew Chua, a 28-year-old graduate student who lives just steps from Kohberger’s building, said in the nearly seven weeks since the murders, he hadn’t noticed anything “at all” unusual in the neighborhood.

“I didn’t know about this issue, it’s a very quiet, very nice place to live,” said Chua, who did not recognize Kohberger’s photo. “Now, I’m like, ‘Maybe I should stay home.’”

Shawn Domgaard, a 36-year-old PhD student at WSU, said the news of the arrest just a stone’s throw from his home is “hard to process.” 

“It’s just so, like I said, a high contrast to what we’re used to,” said the Utah native and father of three young kids told Fox. “It feels like it’s happening far away even though it’s literally in my backyard.” 

Kohberger has been charged with murdering Kaylee Goncalves, 21, Madison Mogen, 21, Xana Kernodle, 20, and Ethan Chapin, 20, who were found stabbed to death in their beds in their off-campus home on Nov. 13.

More information on the murders and the investigation that led to Kohberger’s arrest will remain sealed in a probable cause affidavit until he’s extradited back to Idaho, Prosecutor Thompson told reporters at a press conference Friday, citing Idaho state law.

Kohberger is being held without bond in Monroe County, Pa. He has an extradition hearing on Jan. 3.