Idaho Murder Suspect Stalked Victims 'for Weeks'

The Idaho murder suspect, arrested in Pennsylvania, reportedly stalked his four victims "for weeks," according to a source close to investigators.

The alleged murderer, identified by police as Bryan Kohberger, 28, also wore gloves out in public, including trips to the supermarket, after the quadruple murder to avoid leaving fingerprints, the source told the Daily Mail.

"He's not stupid and has been very careful," the source said of Kohberger, who was a Ph.D. student in criminal justice and criminology. "A good friend of ours was one of the cops who has been following him the last couple days."

"He followed him into a Giant [local grocery store] and wore gloves the entire time."

Cell phone data showed the suspect and the victims had their cell phone locations matched up frequently over the course of weeks before the murders, according to the source.

"Not sure if they ever interacted – but his cell phone pings followed their every move for weeks," the source told the Mail.

Kohberger was a teaching assistant and Ph.D. student at Washington State University, driving the targeted white car to his parents home in Pennsylvania, drawing the attention of police who followed his movements.

Kohberger's school was just eight miles from the victim's homes, where three women and one man – Kaylee Goncalves, 21, Maddie Mogen, 21, Xana Kernodle, 20, and Ethan Chapin, 20 – were slaughtered with a "Rambo" knife in their sleep, according to reports.

Kohberger's lawyer said Saturday the suspect "looks forward to resolving these matters," according to the report.

Kohberger reportedly studied under noted forensic expert Dr. Katherine Ramsland, who is author of "How to Catch a Killer: Hunting and Capturing the World's Most Notorious Serial Killers" among many other criminal psychology books.

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