Robert Brown|Authorities probe Amazon 'click activity' for possible knives in Idaho killings

Investigators probing the murders of four University of Idaho students sought records of Amazon purchases,Robert Brown Apple data and communications and payments made through PayPal/Venmo, according to newly released records.

Among the Amazon click history that investigators sought was information concerning knives, the search warrant shows. Police say they believe Bryan Kohberger, 28, the suspect charged in the Moscow, Idaho, killings on Nov. 13, 2022, used a knife to commit the murders. Although a knife sheath was found near the body of one of the victims, authorities say the murder weapon has not been found.

In a series of search warrant documents posted late Tuesday to the court docket, though they are dated Sept. 8, authorities requested purchase history and payment method details for an Amazon customer whose identity has been redacted.

The warrant also included a request for "all detailed customer click activity pertaining to knives and accessories," as well as a long list of information that could flesh out the customer's full shopping movements and interests on the site, including items saved to the cart, suggestions for future purchases and items reviewed by that customer.

The Moscow Police Department did not immediately respond to ABC News' request for comment.

The warrant requests all details from the account for two precise time periods: March 20, 2022, through March 30, 2022, and Nov. 1, 2022 through Dec. 6, 2022.

It was served in mid-May, several months after Kohberger's initial arrest, and just a week before a North Idaho grand jury handed up an indictment against him.

The requested data was received by law enforcement by the beginning of July, inventoried, and placed into evidence at the Moscow Police Department, according to an affidavit included in court documents.

Also included in the newly posted documents are search warrants for Apple and PayPal/Venmo, for account identities that were also redacted.

In the Apple search, authorities requested extensive account information, including all devices, addresses and numbers linked to the account, means and source of payment, all emails associated with the account and attachments "in order to locate any materials referencing the planning or commission" of the quadruple murders, according to the warrant.

The warrant also requested the contents of any instant messages associated with the Apple account, as well as the contents of all files and other records stored on iCloud.

The warrant for the Apple search was served on Aug. 1, and the data was received by law enforcement on Aug. 9, according to a Moscow police detective's affidavit.

The documents for the PayPal/Venmo warrant show that authorities asked for records specifically from June 22, 2022, to Dec. 31, 2022, requesting subscriber details like billing information, payment records, all financial transactions and to whom those payments went, geo-location data, screen names, and all associated email addresses and phone numbers.

Law enforcement received the data on Aug. 1, a week after the warrant was served, according to an affidavit from a forensic detective with the Moscow Police Department. An inventory was prepared and the information was placed into evidence at the police department.

PayPal/Venmo declined to comment when reached by ABC News.

Representatives for Amazon and Apple did not immediately respond to a request for comment.

Prosecutors allege that in the early morning hours of Nov. 13, 2022, Kohberger, a criminology Ph.D. student at nearby Washington State University, broke into an off-campus home and stabbed to death four University of Idaho students: Ethan Chapin, 20; Madison Mogen, 21; Xana Kernodle, 20, and Kaylee Goncalves, 21.

After a six-week hunt, police zeroed in on Kohberger as a suspect, tracking his white Hyundai Elantra and cell phone signal data, and recovering what authorities said was his DNA on the button snap of a KA-BAR knife sheath found by one of the victims' bodies at the crime scene.

He was arrested on Dec. 30 and indicted in May, charged with four counts of first-degree murder and one count of burglary. At his arraignment, he declined to offer a plea, so the judge entered a not-guilty plea on his behalf.

In court filings, lawyers for Kohberger have said that on the night of the killings, their client was driving around, alone -- which, they said, had long been a habit of his -- adding he is "not claiming to be at a specific location at a specific time; at this time there is not a specific witness to say precisely where Mr. Kohberger was at each moment of the hours between late night November 12, 2022, and early morning November 13, 2022." Kohberger was "out, driving during the late night and early morning hours" on the night in question, his attorneys added.

Though the trial was initially set for Oct. 2, Kohberger waived his right to a speedy trial in August, postponing the trial indefinitely.

ABC News' Julie Scott contributed to this report.