HARRISBURG, Pa. (AP) — Authorities in Pennsylvania arrested a suspect in the killings of four University of Idaho students who were found stabbed to death in their beds more than a month ago, local Police Chief James Fry said Friday.

The killings initially mystified law enforcement and shook the small town of Moscow, Idaho, a farming community of about 25,000 people that had not had a murder for five years. Fears of a repeat attack prompted nearly half of the University of Idaho’s over 11,000 students to leave the city and switch to online classes.

Bryan Christopher Kohberger, 28, was arrested early Friday morning by the Pennsylvania State Police at a home in Chestnuthill Township, authorities said. Latah County Prosecutor Bill Thompson said investigators believe Kohberger broke into the students’ home “with the intent to commit murder.”

Kohberger is being held without bond in Pennsylvania and will be held without bond in Idaho once he is returned, Thompson said, and the affidavit for four charges of first-degree murder in Idaho will remain sealed until he is returned. He is also charged with felony burglary in Idaho, Thompson said. An extradition hearing is scheduled for Tuesday.

Kohberger is a PhD student in the Department of Criminal Justice and Criminology at Washington State University. He is also a teaching assistant for the university’s criminal justice and criminology program, according to WSU’s online directory. University police assisted Idaho law enforcement in executing search warrants at Kohberger’s home and office on campus, the university said. WSU officials did not immediately respond to a request for comment about Kohberger’s work as a teaching assistant.

WSU is a short drive across the state line from the University of Idaho. The two universities are partners in several academic programs, and students sometimes attend classes and seminars or work at the neighboring schools. That doesn’t appear to be the case with Kohberger: University of Idaho President Scott Green wrote in a memo to students and employees on Friday evening that the Idaho school had no record of him.

Kohberger graduated from Northampton Community College in Pennsylvania with an associate of arts degree in psychology in 2018, said college spokesperson Mia Rossi-Marino. DeSales University in Pennsylvania said that he received a bachelor’s degree in 2020 and completed graduate studies in June 2022.

The Idaho students — Kaylee Goncalves, Madison Mogen, Xana Kernodle and Ethan Chapin — were stabbed to death at a rental home near campus sometime in the early morning hours of Nov. 13.

Investigators were unable to name a suspect or locate a murder weapon for weeks.

But the case appeared to break open after law enforcement asked the public for help finding a white Hyundai Elantra sedan seen near the home around the time of the killings. The Moscow Police Department made the request Dec. 7, and by the next day had to direct tips to a special FBI call center because so many were coming in. By mid-December, investigators were working through nearly 12,000 tips and had identified more than 22,000 vehicles matching that make and model.

“We are still looking for the weapon,” Fry said. “I will say that we have found an Elantra.”

Fry was emotional as he announced the arrest, calling the victims by their first names. The chief has said in the past that everyone on the force feels strongly about solving the crime, at times choking up when discussing the impact on the victims’ families and the close-knit rural community.

Goncalves, 21, of Rathdrum, Idaho; Mogen, 21, of Coeur d’Alene, Idaho; Kernodle, 20, of Post Falls, Idaho; and Chapin, 20, of Conway, Washington, were members of the university’s Greek system and close friends. Mogen, Goncalves and Kernodle lived in the three-story rental home with two other roommates. Kernodle and Chapin were dating and he was visiting the house that night.

Autopsies showed all four were likely asleep when they were attacked. Some had defensive wounds and each was stabbed multiple times. There was no sign of sexual assault, police said.

Chief Fry said they’re still “putting all the pieces together” to determine motive.

Police said Thursday the rental home would be cleared of “potential biohazards and other harmful substances” to collect evidence starting Friday morning. It was unclear how long the work would take, but a news release said the house would be returned to the property manager upon completion.

Shanon Gray, an attorney representing Goncalves’s father, Steve Goncalves, said law enforcement officials called the family last night to let them know about the arrest, but gave no additional information about how or why they believe he might be connected to the murders.

“Obviously they’re relieved that someone has been arrested,” Gray said. “You guys know about as much as we do right now.”

Ben Roberts, a graduate student in the criminology and criminal justice department at WSU, described Kohberger as confident and outgoing, but said it seemed like “he was always looking for a way to fit in.”

“It’s pretty out of left field,” he said of the news Friday. “I had honestly just pegged him as being super awkward.”

Roberts started the program in August — along with Kohberger, he said — and had several courses with him. He described Kohberger as wanting to appear academic.

“One thing he would always do, almost without fail, was find the most complicated way to explain something,” he said. “He had to make sure you knew that he knew it.”

Ethan Chapin’s family emailed a statement after the press conference. “We are relieved this chapter is over because it provides a form of closure. However, it doesn’t alter the outcome or alleviate the pain,” the family wrote. “We miss Ethan, and our family is forever changed.”

The Chapin family also thanked the University of Idaho and the Sigma Chi fraternity where Ethan was a member for their support.

“We also appreciate the outpouring of kind words from so many others, which we’ll need as we enter the next chapter of this nightmare,” the family wrote.

The case enticed online sleuths who speculated about potential suspects and motives. Safety concerns also had the university hiring an additional security firm to escort students across campus and the Idaho State Police sending troopers to help patrol the city’s streets.

Kohberger was arrested in eastern Pennsylvania in the Pocono Mountains. No lawyer for Kohberger was listed in court documents and phone calls to the county public defender’s office went answered Friday.