Police did not disclose a motive or what led them to their suspect.

ByEmily ShapiroAaron Katersky, and Josh Margolin
December 31, 2022, 7:45 AM

A 28-year-old graduate student was arrested Friday morning in Pennsylvania’s Pocono Mountains in connection with the November murders of four University of Idaho students, police said, but many details of the case still remain a mystery.

The suspect, Bryan Kohberger, is a graduate student at Washington State University, located less than 10 miles away from the University of Idaho, Moscow Police Chief James Fry said at a Friday news conference.

Law enforcement sources told ABC News that police identified Kohberger as a suspect, at least in part, by using DNA technology, and police then tracked the grad student to Pennsylvania through his car.

PHOTO: This photo provided by Monroe County (Pa.) Correctional Facility shows Bryan Kohberger.
This photo provided by Monroe County (Pa.) Correctional Facility shows Bryan Kohberger. Arrest paperwork filed by Pennsylvania State Police in Monroe County Court, on Dec. 30, 2022, said Kohberger, 2…
Monroe County (Pa.) Correctional Facility via AP

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Sources said the FBI had been watching the house for several days before a specialized team of state troopers and federal agents moved in around 2 a.m. Friday.

Police did not disclose a motive or what led them to their suspect. The probable cause affidavit, which details the reasons for Kohberger’s arrest, is sealed and cannot be released until he returns to Idaho, Latah County Prosecutor Bill Thompson said.