Authorities suspect that the man charged with an Idaho quadruple homicide tried to destroy evidence before being arrested.

A source familiar with the investigation into Bryan Kohberger confirmed as such, speaking about the case to CNN.

Police believe that Kohberger “cleaned his car, inside and outside, not missing an inch" in the days preceding his arrest last month.

The source indicates that the authorities concluded Kohberger had cleaned his Hyundai Elantra during four days they spent surveilling the suspect.

Kohberger traveled from Washington to his parents' residence in Pennsylvania for the holidays, driving his white Hyundai Elantra.

Law enforcement assigned to monitor Kohberger observed him disposing of garbage in his family's neighbors' disposal bins -- while wearing surgical gloves, according to the source cited by CNN.

Police proceeded to obtain garbage from the Kohberger family's trash bins, later sending the potential evidence to the Idaho State Lab for analysis.

Their role was to monitor for evidence as well as wait for a potential warrant for Kohberger's arrest, the news outlet reported.

It appears possible that DNA obtained from Kohberger's trash could have been used to match his genetic profile with that of the suspected killer.

A Pennsylvania State Police SWAT unit ultimately broke down the windows and doors of the Kohberger home in an unconventional operation to arrest the suspect, CNN said.

The method, called "dynamic entry," is only used for the most dangerous criminal suspects, according to the source.

DNA evidence is crucial to the prosecution's case against Kohberger.

The state alleges that DNA matching Kohberger's genetic profile has been found at the scene of a bloody November stabbing spree, and on the sheath of a K-Bar knife left at the home of the four murdered University of Idaho students.

The location of Kohberger's vehicle, as well as signals emitted by his cell phone, are also evidence that prosecutors detailed in a probable cause affidavit released to the public after the suspect's extradition to Idaho, according to NPR.

Kohberger has maintained his innocence in the face of four first-degree murder charges and has claimed that he'll be eventually exonerated.

The Washington State University criminology Ph.D student was denied bail in his first Latah County, Idaho, court appearance.

The family of one victim killed in the home invasion has expressed their preference for the death penalty in the event of Kohberger's eventual conviction.

This article appeared originally on The Western Journal.