Bryan Christopher Kohberger
Bryan Christopher Kohberger, 25, poses for a jail booking photograph at the Monroe County Correctional Facility in Stroudsberg, Pennsylvania, U.S. December 30, 2022. Image Credit: Reuters

LOS ANGELES: US police investigating the frenzied stabbing of four students at a small Idaho university said Friday they had arrested a man on the other side of the country.

The brutal killings in mid-November left the college town of Moscow in shock as residents struggled to come to grips with the first murders there in several years.

The students - Kaylee Goncalves, 21; Madison Mogen, 21; Xana Kernodle, 20; and Kernodle's boyfriend, Ethan Chapin, 20 - were likely to have been asleep when they were stabbed multiple times, detectives have said.

Autopsies revealed some of them had defensive wounds, indicating they tried to protect themselves as their killer struck.

The slayings triggered a massive manhunt and appeals for help from the public, as well as a rush of amateur online sleuthing as armchair detectives tried to piece together scant clues released by investigators.

Thousands of tips flooded in to police in the far western state, and on Friday, Moscow Police Chief James Fry said they had made a breakthrough - 4,000 kilometers (2,500 miles) away.

"Last night in conjunction with the Pennsylvania State Police, Federal Bureau of Investigation, detectives arrested 28-year-old Bryan Christopher Kohberger, in Albrightsville, Pennsylvania on a warrant for murder," he told reporters.

Fry said Kohberger is a graduate student at Washington State University, whose campus is a short distance from Moscow.

An archive search of the university's website reveals Kohberger to have been a PhD candidate in the department of criminal justice and criminology.

"Due to Idaho State law, we are limited in what information we can release today, until Kohburger has his initial appearance in Idaho," Fry said.

No motive was revealed for the killings, and police are still searching for the murder weapon.

US media reported that Kohberger was arrested at his parents' home.

He has made one appearance in court in Pennsylvania, and is due to appear again on Tuesday.

Bill Thompson, Latah County prosecutor, said Kohberger was being held without bail on suspicion of four counts of first degree murder, and one count of felony burglary.

If he opts not to return voluntarily to Idaho, the state will seek to extradite him from Pennsylvania, he said.