A man accused of stabbing to death four university students in their beds in Idaho last year has refused to enter a plea after appearing in court.

Criminology student Bryan Kohberger, 28, appeared at Latah County courtroom on Monday.

District Judge John Judge entered a not-guilty plea on his behalf.

Last week, a grand jury formally charged Kohberger with four counts of murder and one count of burglary.

He is alleged to have killed housemates Kaylee Goncalves, 21, Madison Mogen, 21, Xana Kernodle, 20, and Kernodle’s boyfriend, Ethan Chapin, 20, in the early hours of 13 November last year.

Two other housemates, who were at home at the time of the attacks and were sleeping in ground-floor level bedrooms, say they slept as the murders took place.

When they woke up the next morning they summoned other friends to the house and one of those friends called police believing the housemates to be unconscious.

It was only then they discovered the horrific crime scene.