Bryan Kohberger, the suspect in the murder of four college students, is already in Idaho after being extradited from Pennsylvania

Suspect arrested in Idaho student homicide 1:04

(CNN) --

Bryan Kohberger, the man accused of killing four University of Idaho students in November, has returned to the state after accepting extradition from his home state of Pennsylvania.

Police escorted Kohberger to the Latah County Jail Wednesday night.

He was booked on four counts of murder and one count of robbery, according to jail records.

Early Wednesday, an online flight tracker showed that the Pennsylvania State Police plane believed to be carrying Kohberger had arrived at Pullman-Moscow Regional Airport, across the border in Washington state.

A CNN crew at the airport saw Idaho police vehicles at the scene.

Bryan Kohberger leaves a Pennsylvania courthouse Tuesday after an extradition hearing in Stroudsburg.

(Mark Makela/Reuters)

Kohberger was turned over from the Monroe County Correctional Center to Pennsylvania State Police authorities, jail warden Garry Haidle told CNN.

State Police declined to comment on any prisoner transports, according to their policy.

Kohberger was arrested Friday in Pennsylvania, nearly seven weeks after 21-year-old Kaylee Goncalves;

Madison Mogen, 21;

Xana Kernodle, 20, and Ethan Chapin, 20, were found fatally stabbed on November 13 at an off-campus home in Moscow, Idaho.

Authorities have yet to reveal key details of the case, such as whether the suspect knew the victims and what his motive may have been.

• What we know (and don't yet) about the suspect in the murder of college students in Idaho

Investigators zeroed in on Kohberger as a suspect after tracking down the owner of a white Hyundai Elantra car, who had been seen in the area of ​​the crimes, according to two law enforcement sources briefed on the investigation.

In addition, their DNA was compared to genetic material recovered from the house where the students were killed, the sources said.

The suspect recently finished his first semester as a doctoral student in the criminal justice program at the Washington State University campus in Pullman, about a 15-minute drive west of Moscow.

New details in the Idaho stabbing investigation 2:28

He drove home to Pennsylvania over the holidays with his father, Monroe County Chief Public Defender Jason LaBar said.

The father and son arrived around December 17.

The white Elantra that authorities had been looking for in connection with the murders was found at the home of Kohberger's parents, LaBar said.

An FBI surveillance team tracked Kohberger for four days before his arrest as police worked with prosecutors to develop sufficient probable cause to obtain a warrant, the two law enforcement sources said.

The probable cause affidavit, which would contain information to justify the suspect's arrest, remains sealed until he is brought before an Idaho court.

A court order prohibits the prosecution and defense from commenting beyond public records.

CNN's Josh Campbell, Jason Kravarik, Ken Tillis, Taylor Romine and Holly Yan contributed to this report.

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