Pennsylvania police are sifting through cold cases for possible links to Bryan Kohberger

Northampton County District and Lehigh County started looking for links between unsolved cases and Mr Kohberger following his 30 December arrest

Two law enforcement offices in Pennsylvania are reportedly sifting through cold case files in search of any potential links to Idaho murders suspect Bryan Kohberger.

Northampton County District and Lehigh County started looking for links between unsolved cases and Mr Kohberger following his 30 December arrest, King5 reported. The Washington State University PhD student is accused of murdering Kaylee Goncalves, Xana Kernodle, Madison Mogen and Ethan Chapin on 13 November in Moscow, Idaho.

Mr Kohberger, originally from Pennsylvania, was a student at Northampton Community College in Bethlehem before he went on to spend four years studying criminology at DeSales University in Lehigh County. Prosecutors in the two Keystone State counties told King5 that although no links have emerged so far, their offices are still working through cold cases databases.

“Your natural question is to start wondering, ‘is this guy wanted?’” Northampton County District Attorney Terence Houck told the network. “Is his name out there? Did he do anything here in [my] county?”

Mr Houck said his department had used Mr Kohberger’s height, weight and the alleged Idaho killer’s method of operation to compare with old cases - to no avail so far.

Lehigh County District Attorney Jim Martin also told King5: “The first thing I did was ask the director of the RIC [Regional Intelligence and Investigation Center] to see if we had any contact with Mr Kohberger ... [We] have no unsolved homicides that in any way meet the modus operandi of this event out in Idaho,”

Mr Martin said his office sorted through a database with more than six million police reports and case files, only finding one instance in which Mr Kohberger called 911 when his car locked behind a parked gate. Mr Martin said that Mr Kohberger’s exchange with law enforcement was uneventful and that he was apologetic.

Following several days of a surveillance operation by the FBI, Mr Kohbergerwas arrested at his parent’s home in Monroe County pm 30 December. At the time, police said he had no previous criminal history.

It has since emerged that Mr Kohberger was facing disciplinary action in his teaching assistant job at WSU around the time of the murders of the four University of Idaho students – before he was ultimately fired from the position days before his arrest.

According to an affidavit released last month, cellphone data places Mr Kohberger close to the home of the murders at around 9am on 13 November – suggesting that he returned to the scene of the crime just hours after allegedly murdering the four victims at around 4am.

Police also said that his DNA was also found on a knife sheath left behind at the scene by the killer and his white Hyundai Elantra was caught on surveillance footage at the crime scene at the time of the murders, the affidavit reveals.

Ethan Chapin, 20, Madison Mogen, 21, Xana Kernodle, 20 and Kaylee Goncalves, 21 (Instagram/Kaylee Goncalves)

One of the victims’ surviving roommates was also able to partially describe the killer to investigators after she came face to face with him in the aftermath of the murders.

Acquaintances of Mr Kohberger also spoke with King5 and recounted the suspected murderer’s struggles as a teen. Jack Baylis, who met Mr Kohberger when they were eighthgraders, told the Network that Mr Kohberger struggled with heroin addiction, as other of his former friends have previously claimed.

“He’s always been kind of fascinated with kind of how the how the brain works and how people think and why they do what they do,” Mr Baylis said. “I want to say he wanted to be a cop since he was younger.”

Vernard James also told King5 that while working on a class project with Mr Kohberger at DeSales, he realised the criminology student could be “manipulative” and “cold”

“We’re approaching the due date and I was feeling like I was left out to dry,” Mr James said, adding that Mr Kohberger gave him a “very intense stare” when confronted. “I remember that. I’ll never forget that looking right into my soul almost, you know, as we were having this back and forth.”

James said Kohberger was dismissive of his complaint and accepted no responsibility as the project leader.

At DeSales, Mr Kohberger studied under renowned forensic psychologist Katherine Ramsland who interviewed the BTK serial killer and co-wrote the book Confession of a Serial Killer: The Untold Story of Dennis Rader, the BTK Killer with him.

He also carried out a research project “to understand how emotions and psychological traits influence decision-making when committing a crime”.

Mr Kohberger is set to appear in court for a preliminary hearing on 25 June.