The DNA of Bryan Kohberger, the man accused of murdering four University of Idaho students, was discovered on a knife sheath that the killer left at the crime scene, according to investigators.

On 5 January, court documents in support of Mr Kohberger’s arrest were released and revealed new details about the incident.

One document says that the killer left a tan leather sheath from the murder weapon on victim Madison Mogen’s bed next to her body.

The sheath allegedly contains the DNA of a single male – the 28-year-old PhD student now charged with the murders.

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