A 28-year-old man, Bryan Kohberger, was arrested Friday morning in Pennsylvania's Pocono Mountains in connection with the murders of four University of Idaho students, law enforcement sources told ABC News.
Kohberger is a graduate student at Washington State University, located about 10 miles away from the University of Idaho, Moscow Police Chief James Fry said at a Friday news conference.
Sources said that authorities knew who they were looking for and had tracked Kohberger down to Pennsylvania.
A SWAT team entered the location where he was staying in order to take him into custody Friday. He was arrested for four counts of first-degree murder and burglary, Latah County Prosecutor Bill Thompson said.
Police did not disclose a motive or what led them to their suspect. The probable cause affidavit, which details the reasons for his arrest, is sealed and will not be released until he returns to Idaho, Thompson said.
Fry would not say if police are looking for more suspects, but he said, "I do believe our community is safe."
Kohberger appeared before a judge in Pennsylvania Friday morning and is being held without bond, Thompson said. He's scheduled to return to court on Tuesday and will be appointed a public defender, Thompson said.
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It's been over six weeks since roommates Kaylee Goncalves, Madison Mogen and Xana Kernodle, as well as Kernodle's boyfriend, Ethan Chapin, were all stabbed to death in the girls' off-campus house in the early hours of Nov. 13.
Two other roommates -- who police said are not suspects -- survived and likely slept through the murders, according to officials. The survivors were on the ground floor while the four victims were on the second and third floors.
The murder weapon has not been recovered, the chief said.
The family of Goncalves told ABC News on Friday that they don't know Kohberger and are "happy, relieved and thankful" that there's been an arrest.
"No arrest will ever bring back these young students. However, we do believe justice will be found through the criminal process," the chief said.
Moscow's deputy city supervisor, Tyler Palmer, called the arrest a "tremendous sigh of relief for a community holding its breath for more than six weeks."
Police have been urging the public to come forward with information.
It's been weeks since police and city officials have gathered for a news conference, choosing instead to release small updates through social media. This new announcement comes as University of Idaho students are away from campus for winter break.
Editor's note: ABC News first reported the suspect was 25 years old before updating the suspect's age to 28.