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Bryan Christopher Kohberger, the suspect arrested in connection to the murders of four University of Idaho students, appeared before a judge on Thursday morning shortly after chilling details were released related to the killings. 

WHO IS BRYAN KOHBERGER? 

Kohberger, 28, was charged with four counts of first-degree murder and one count of felony burglary for the Nov. 13 quadruple homicide involving college students Kaylee Goncalves, Madison Mogen, Ethan Chapin, and Xana Kernodle. Dozens of law enforcement officers investigated the case for over six weeks before news broke of Kohberger’s Friday arrest. 

Kohberger was extradited from Monroe County, Pennsylvania, where he was arrested at his home, on early Wednesday morning. The private plane that carried him arrived in Pullman, Washington several hours later. 

UNIVERSITY OF IDAHO STUDENT STABBINGS TIMELINE

A mug shot head on and side profile of Idaho murder suspect Bryan Kohberger

Bryan Kohberger, 28, is accused of killing Ethan Chapin, Xana Kernodle, Kaylee Goncalves and Madison Mogen. (Latah County Sheriff's Office)

The accused killer is being represented by Anne Taylor, chief public defender of Kootenai County.

Monroe County Chief Public Defender Jason LaBar told NBC News that the Washington State University Ph.D. student-turned-accused mass murderer told him he believes he will be found not guilty.

Moscow, Idaho college killings suspect Bryan Christopher Kohberger seen in mugshot

Bryan Kohberger was arrested Friday in connection to the murders of four University of Idaho students based on an active arrest warrant for first-degree murder issued by the Moscow Police Department and Latah County Prosecutor’s Office. (Monroe County Correctional Facility via AP)

"He believes he’s going to be exonerated. That’s what he believes," said LaBar, who had visited Kohberger four times since his arrest. "Those were his words. He’s been very easy to talk to. Actually, he’s in a calm demeanor."

IDAHO MURDERS: BRYAN KOHBERGER HELD WITHOUT BOND IN STUDENT SLAYINGS AMID CHILLING NEW DETAILS

Michael Mancuso, a prosecutor in Monroe County, said Tuesday he believed Kohberger waived extradition to Idaho because of a "need to know" how investigators established probable cause after the crime.

Suspect in red jumpsuit is handcuffed and escorted by law enforcement officer

Bryan Kohberger exits Monroe County Court House in Stroudsburg, PA Tuesday, January 5, 2023 after his extradition hearing. (The Image Direct for Fox News Digital)

"Having read those documents and the sealed affidavits of probable cause, I definitely believe that one of the main reasons the defendant chose to waive extradition and hurry his return back to Idaho was the need to know what was in those documents. So, that's a significant development," Mancuso said.

WHAT IS BRYAN KOHBERGER’S BACKGROUND?

Moscow, Idaho suspect in custody, Bryan Christopher Kohberger

Bryan Christopher Kohberger, 28, was arrested in connection to four murders in Moscow, Idaho. (Washington State University)

Kohberger, who is originally from eastern Pennsylvania, was studying criminal justice at Washington State University and was allegedly hiding out at his parents' home in after the killings. 

The police affidavit revealed that last fall, Kohberger applied for an internship with the Pullman Police Department. In his application essay, he said he was interested in helping police more efficiently collect and analyze technological data in public safety operations.

Bryan Kohberger's sophomore and senior photos side by side

A side by side of Kohberger's sophomore Pleasant Valley High School yearbook photo and his senior year.  (Stephanie Pagones/Fox News Digital)

He attended Pleasant Valley High School in Brodheadsville, Pennsylvania, where he graduated in 2013. Photos from his high school yearbooks show he made a stark physical transformation from sophomore to senior years, and allegedly aspired to be an Army Ranger. 

IDAHO MURDER VICTIMS' ROOMMATE HEARD CRYING, SAW MAN IN MASK MORNING OF KILLINGS: COURT DOCS

Byran Kohberger in black and white photo

A yearhbook photo of Bryan Kohberger in a high school law enforcement class doing a push up.  (Stephanie Pagones/Fox News Digital)

Kohberger appears to have worked in the Pleasant Valley School District as a "casual security officer" as recently as August 2021, according to board of education meeting minutes. 

The suspect has roots in the Keystone state going back at least to 2013 when he registered as a Libertarian in Albrightsville, public records show. He did not appear to have a criminal record.

Bryan Kohberger's high school in Pennsylvania

Pleasant Valley High School in Brodheadsville,PA on January 4, 2023.  (Stephanie Pagones/Fox News Digital)

He has two sisters, including one that works as marriage and family therapist in New Jersey. 

Kohberger graduated from DeSales University in Allentown with a bachelor's degree in 2020 and Master of Arts in Criminal Justice in June 2022, according to a commencement program.

DeSales University issued a statement in response to Kohberger's arrest. "As a Catholic, Salesian community, we are devastated by this senseless tragedy," the statement says. "Our thoughts and prayers are with the victims' families during this difficult time."

He then went on to become a PhD student at the department of criminal justice and criminology, according to the WSU website. Kohberger had completed his first semester, which ended shortly after the killings, before his arrest.

Apartment building near WSU

Crime scene tape surrounds an entrance to the Pullman apartment searched Friday morning. (Stephanie Pagones/Fox News Digital)

IDAHO MURDER SUSPECT KOHBERGER'S PENNSYLVANIA CLASSMATES SAY HE WAS ‘BRIGHT,’ AWKWARD, BULLIED IN SCHOOL

Kohberger had allegedly been working as a teacher’s assistant prior to his arrest, and lived in on-campus student and family housing in WSU’s Steptoe Village. 

"On behalf of the WSU Pullman community, I want to offer my sincere thanks to all of the law enforcement agencies that have been working tirelessly to solve this crime," said Elizabeth Chilton, chancellor of the WSU Pullman campus and WSU provost. "This horrific act has shaken everyone in the Palouse region."

Investigators from the Idaho State Police, WSU Police were joined by Latah County Prosecutor Bill Thompson for the execution of a search warrant inside Kohberger’s second-story apartment on Friday morning. Investigators also searched his WSU Pullman office. 

WHO ARE BRYAN KOHBERGER’S PARENTS? 

bryan kohberger parents

Bryan Kohberger's father, Michael Kohberger exits Monroe County Court House in Stroudsburg, PA on Tuesday, January 3, 2023 after his son's extradition hearing.  (The Image Direct for Fox News Digital)

Koherger’s parents, Michael and Maryann, and his sisters, sat in the second row of the Monroe County Courthouse during Kohberger’s extradition hearing on Tuesday in Stroudsburg, Pennsylvania. 

His father nodded or shook his head during parts of the brief hearing, and waved at his son, who muttered something to his loved ones, before he was led out of the courtroom. 

His sisters appeared visibly upset, and at times distraught, during the hearing. A court officer brought Kohberger’s weeping sister a box of tissues as the hearing commenced. 

Jason LaBar, the chief public defender of Monroe County, Pennsylvania is seen leaving court Tuesday, January 3, 2023. (The Image Direct for Fox News Digital)

Kohberger’s mother stared straight ahead or held her head down during the court proceedings. His parents covered their faces with hats or their jackets as they exited the courthouse shortly thereafter Tuesday. 

After his arrest, Kohberger’s family was reportedly "shocked" and skeptical of his alleged involvement in the killings. 

A woman with a black coat on with fur-lined hood pulled over her face is helped to the car by two younger woman holding her shoulders

Bryan Kohberger's mother, Maryann Kohberger exits Monroe County Court House in Stroudsburg, PA on Tuesday, January 3, 2023 after her son's extradition hearing. (The Image Direct for fox News Digital)

"They don’t believe it to be Bryan. They can’t believe this," LaBar told NBC News. "They’re obviously shocked. This is certainly completely out of character, the allegations, and really they’re just trying to be supportive with the understanding that these four families have suffered loss."

In a subsequent statement released by LaBar on their behalf, Kohberger’s family wrote: "We have fully cooperated with law enforcement agencies in an attempt to seek the truth and promote his presumption of innocence rather than judge unknown facts and make erroneous assumptions."

A woman with a black coat on with fur-lined hood pulled over her face walks alongside a younger woman

Bryan Kohberger's mother, Maryann Kohberger exits Monroe County Court House in Stroudsburg, PA on Tuesday, January 3, 2023 after her son's extradition hearing. Her son is charged with the murder of four University of Idaho students in November last year. (The Image Direct for fox News Digital)

They added that they would "continue to let the legal process unfold and as a family we will love and support our son and brother."

They said there were "no words that can adequately express the sadness we feel, and we pray each day for them." 

"We respect privacy in this matter as our family and the families suffering loss can move forward through the legal process."

WHAT ARE THE KNOWN FACTS ABOUT THE IDAHO MURDER CASE? 

University of Idaho victims Madeline Mogen, Ethan Chapin, Xana Kernodle, and Kaylee Goncalves

The victims of Nov. 13 University of Idaho massacre.  (Instagram @xanakernodle / @maddiemogen / @kayleegoncalves)

The college town of Pullman, Washington, is about eight miles from the King Road home where Goncalves, 21, Mogen, 21, Chapin, 20, and Kernodle, 20, were stabbed to death.

The victims’ savaged bodies were discovered inside the three-story King Road residence just before noon on Nov. 13. Goncalves, Kernodle and Mogen lived at the address, which is located just one block from the University of Idaho campus and within eyeshot of some fraternity houses.

Officials have said they believe the victims were asleep when they were ambushed between 3 a.m. and 4 a.m. on Nov. 13 inside the home at 1122 King Road. Each victim suffered several stab wounds, and some showed signs of trying to defend themselves. Investigators said they were attacked with a large fixed-blade knife

University of Idaho home where four students were killed is snowed in

General views of the home in Moscow, Idaho, Sunday, Dec. 4, 2022, where a quadruple homicide took place last month. (Hunter Richards for Fox News Digital)

Police have said the attack was carried out on the second and third floors. Two other roommates were on the bottom floor of the home and were unharmed, police said.

Moscow police officers responded around 11:58 a.m. to a report of an "unconscious person" at the address, but several people had gathered at the crime scene by the time police arrived, officials said.

The 911 call "originated from inside the residence" and came from one of the surviving roommates' cellphones, police said. Multiple people allegedly spoke to the dispatcher before officers arrived.

Idaho victims last photo

Ethan Chapin, 20, Xana Kernodle, 20, Madison Mogen, 21, and Kaylee Goncalves, 21, along with the women's two other roommates in Kaylee Goncalves' final Instagram post, shared the day before the slayings. (@kayleegoncalves/Instagram)

Police also analyzed 113 pieces of physical evidence and about 4,000 photos from the scene. 

Moscow police had said they were looking for a white 2011 to 2013 Hyundai Elantra spotted near the King Road residence around the time of the murders. 

Investigators had been sifting through more than 22,000 registered cars that matched their search criteria, according to police.

The Moscow Police Department, along with Idaho State Police and the FBI, had been working feverishly for nearly seven weeks to solve the baffling quadruple homicide.

Memorial and crime scene tape outside Idaho home where students were killed

A Moscow police officer is seen fixing the crime scene tape outside of the home where four University of Idaho students were stabbed to death. (Derek Shook for Fox News Digital)

Kohberger was arrested at about 1:30 a.m. Friday by local police and the FBI at his parents' home in the gated community of Indian Mountain Lake in Albrightsville, Pennsylvania, court and public records show.

A SWAT team descended on the property, which is near several ski resorts and the Pocono Raceway, to take him into custody. The Indian Mountain Lake website informed residents of the FBI raid. 

A white Hyundai Elantra was removed from the home, officials have said. 

WHERE DOES THE IDAHO MURDER INVESTIGATION STAND? 

Bryan Kohberger in orange jumpsuit

Bryan Kohberger, right, who is accused of killing four University of Idaho students in November 2022, is led away following a hearing in Latah County District Court, Thursday, Jan. 5, 2023, in Moscow, Idaho.  (AP Photo/Ted S. Warren, Pool)

Kohberger appeared in court on Thursday morning, when he was ordered held without bond and to refrain from contacting the surviving victims and their friends. 

He faces a maximum of the death penalty for each first-degree murder count, and is due back in court in the coming weeks. He has not yet entered a plea. 

Chilling details included in a probable cause affidavit released Thursday morning revealed that Kohberger allegedly cased the crime scene, and was in the area a dozen times, before carrying out the heinous crimes. He also allegedly returned after the fact. The document further describes how one of the victims' roommates heard and saw someone inside the home, and also heard what sounded like Goncalves saying, "There's someone here."

READ THE PROBABLE CAUSE AFFIDAVIT (WARNING: GRAPHIC DETAILS)

She "then heard a male voice say something to the effect of ‘it’s ok, I'm going to help you,.'" the affidavit states. 

"[A surviving roommate] stated she opened her door for the third time after she heard the crying and saw a figure clad in black clothing and a mask that covered the person's mouth and nose walking towards her," the affidavit goes on. The figure then allegedly passed the woman, who stood in "a frozen shock phase." Investigators believe he then left the scene. 

The Mosow, Idaho, home where four Idaho college students were killed.

The home where four University of Idaho students were murdered Nov. 13.  (Derek Shook for Fox News Digital)

According to the affidavit, a security camera located on a nearby property just 50 feet from Kernodle's bedroom captured "distorted audio of what sounded like voices or a whimper followed by a loud thud" at 4:17 a.m. A dog also began barking numerous times, the document says. 

Kohberger allegedly left behind a tan leather knife sheath laying on the bed next to Mogen's right side. The sheath had "Ka-Bar" and a United States Marine Corps eagle globe and anchor insignia stamped on the outside of it. 

"The Idaho State Lab later located a single source of male DNA (suspect profile) left on the button snap of the knife sheath," the filing says.

Kernodle, who had defensive wounds, was likely awake when she was ambushed, according ot the document. She was on TikTok on her phone at approximately 4:12 a.m.

Kohberger was allegedly captured on surveillance video fleeing the scene in his white 2015 Hyundai Elantra at about 4:20 a.m. But he returned to the crime scene a little after 9 a.m. – three hours before police were called to the house, the affidavit said.

That afternoon Kohberger was allegedly captured on surveillance footage doing some shopping at Albertsons' grocery store in the Pullman area. Cellphone records reveal that the suspect had likely been surveilling the home for weeks.

After the semester wrapped up, Kohberger drove 2,500 miles to Pennsylvania with his father to the family's home in eastern Pennsylvania.

On Dec. 27, agents fished through the Kohberger family trash and sent the evidence to the Idaho State Lab.

The next day, the lab reported that the DNA profile obtained from the trash matched the profile from the knife sheath left at the crime scene. 

Idaho Kohberger route map

Map showing Idaho murder suspect Bryan Kohberger's movement on the morning of Nov. 13 after four University of Idaho students were stabbed in their home. (Google Earth / Fox News Digital)

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Despite the recent arrest, the Moscow Police Department is urging the public to submit any images or information that they think could be important or useful to their investigation. They can do so by calling 208-883-7180, submitting tips through tipline@ci.moscow.id.us and sending digital media here

Fox News' Bradford Betz and Jeremy Copas contributed to this report.