Four people are dead after a Roper Highway crash while another person was struck and killed while walking on the Stuart Highway near Noonamah on Saturday night.

A vehicle carrying five people crashed on a secluded section of the Roper Highway, 85 km from the Stuart Highway intersection, southwest of Mataranka, around 7pm Saturday night, NT Police said.

Responding officers found three females and one male dead at the scene. A male survivor who suffered serious injuries was rushed to Katherine for treatment.

Detectives and forensic officers were working to identify the deceased.

“This is a significant loss of life,” Detective Senior Sergeant Brendan Lindner said.

“Detectives are expected to remain at the crash scene until late afternoon [Sunday]. The Roper Highway remains closed and there are no diversions in place. Motorists are advised not to travel on the Roper Highway today.”

Meanwhile, around 8pm Saturday night, a vehicle struck a pedestrian killing him instantly on the Stuart Highway near the Jenkins Road intersection, with police investigations continuing into the identity of the male victim.

Police said the driver stopped at the scene and called emergency services.

“Police believe the man was walking south and alone at the time. He was wearing dark clothing,” Sit Sgt Lindner said.

“The driver stopped at the scene as lawfully required and contacted police. He tested negative for alcohol and had blood taken for screening for any drugs.”

So far this year, eight people have been killed on NT roads, compared to only one over the same four-week period last year.

Police are calling for anyone with information that could assist either investigation to contact them on 131 444.