Suspected killer Bryan Kohberger was seeking a PhD in criminology and was enrolled in the graduate program at Washington State University. He had recently graduated from DeSales University in Pennsylvania with a degree in criminal justice.

B.K. Norton told the New York Times that they attended graduate studies with Kohberger at WSU -- and quickly noticed some red flags that weren't obvious earlier in the semester after the brutal slayings came to light.

“[Bryan] seemed more upbeat and willing to carry a conversation,” Norton wrote in an email to the NYT. They added Kohberger had a keen interest in forensic psychology.

They said Kohberger had a quiet, but intense demeanor, which made those around him feel uncomfortable. He also passed certain remarks that made it clear he was anti-LGBTQ.

“He sort of creeped people out because he stared and didn’t talk much, but when he did it was very intelligent and he needed everyone to know he was smart,” Norton said.

Kohberger was arrested Friday in Monroe County, PA, after an FBI SWAT team descended on a house where he was staying.

He was charged in Idaho with four counts of first-degree murder in connection with the November 13th fatal stabbings of Kaylee Gonclaves, Maddie Mogen, Xana Kernodle and Ethan Chapin. All four victims were students at the University of Idaho. Police have not disclosed a motive.