Northern Territory Police Fire and Emergency Services are responding to a fatal crash that occurred early this morning in Pine Creek.

Around 3:15am, Joint Emergency Services Communication Centre received reports of a collision along the Stuart Highway involving a two vehicles 40km south of Pine Creek.

Emergency services deployed to the scene and two males were conveyed via Careflight to Royal Darwin hospital in a critical condition.

A 47-year-old male has since succumbed to his injuries and the other remains in a critical condition.

A crime scene has been established and Major Crash Investigation Unit Detectives are investigating the cause of the collision. 

The Stuart Highway is currently closed in both directions and significant delays can be expected.

Police advise motorists to avoid the area.

Police are appealing to anyone who witnessed the crash or has dashcam footage to make contact on 131 444.