Police responded to reports that a woman had stopped breathing near Barkly Homestead on the Barkly Highway in the Avon Downs district about 5.50am on Sunday, April 5 after a car she was in was reportedly hit by a kangaroo.
The 27-year-old woman died at the scene, and a 33-year-old man was arrested shortly after.
Police are seeking any information or dashcam footage from motorists who were in the area at that time.
(Northern Territory Police)
He remains in custody, and it is believed that the pair were in a relationship.
Police allege a male and female were parked in a dark-coloured Jeep Cherokee beside the intersection of the Barkly and Tablelands Highways on Sunday between 1.30am and 5.30am.
Authorities believe that the pair used the Jeep to drive from Gympie, Queensland, to Barkly Homestead between April 1 and April 5.
It is believed that they passed through Ban Ban Springs, Emerald, Winton, Cloncurry, Mt Isa and Camooweal in Queensland.
Police are searching for information or dashcam footage from drivers who were in that area at that time.
Anyone who has seen the vehicle is urged to contact police or make an anonymous report through Crime Stoppers on 1800 333 000.
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