Idaho Murders Update: Police Chief 'Certain' Bryan Kohberger Is 'Our Guy'

Moscow, Idaho, Police Chief James Fry is confident that Bryan Kohberger is the real suspect in the killings of four University of Idaho students.

Kohberger, 28, is accused of stabbing to death University of Idaho students Ethan Chapin, Xana Kernodle, Madison Mogen and Kaylee Goncalves in a house near campus on Nov. 13. The graduate student at Washington State University was arrested Friday in his home state of Pennsylvania.

Fry told NBC in an interview Saturday morning that they can't share any details about Kohberger's motive in murdering four Idaho students until after a judge can unseal the probable cause affidavit.

"I am certain this is our guy," the police chief said of Kohberger, KTVB7 reported. "We've got one more phase to go and then the victory will be won."

Moscow Police Captain Anthony Dahlinger echoed Fry's remark, noting that having Kohberger in police custody was a "celebration of sorts" but that it "does not bring these four people back."

Dahlinger said that they are still investigating the case and looking into every aspect but do believe that Kohberger is the correct suspect.

Jason LaBar, an extradition lawyer for Kohberger, told NBC that the suspect could return to Idaho from Pennsylvania as soon as Tuesday evening or Wednesday morning.

LaBar said he expects Kohberger to waive his extradition rights at his trial Tuesday and enter a not-guilty plea in the murder case.

The extradition lawyer said he told Kohberger about various stories and allegations spreading online.

LaBar, who is not the suspect's defense lawyer for the charges that have been brought against him, also said that he thinks Kohberger is mentally stable, despite reports that the suspect had a heroin addiction in the past and experienced bullying from his schoolmates.

In their first public statement, Kohberger's family said they have fully cooperated with the police to "seek the truth and promote his presumption of innocence."

"We will continue to let the legal process unfold and as a family we will love and support our son and brother. We have fully cooperated with law enforcement agencies in an attempt to seek the truth and promote his presumption of innocence," Kohberger's family said.

The suspect's family expressed sadness over the deaths of four Idaho students, adding that they are praying each day for the victims, CNN reported.

Following his arrest, new information revealed that Kohberger had a heroin addiction during his high school and college years and experienced bullying.

During his cross-country trip from Idaho, he was also tracked by a surveillance team of the Federal Bureau of Investigation (FBI).

The suspect is being held in Monroe County, Pennsylvania. Once Kohberger is back in Idaho, the probable cause affidavit can be unsealed, and more information will be available.