Police are investigating whether fatigue played a role in a horror crash that killed two people from the Canberra region on Wednesday.
A ute was travelling along the Monaro Highway near Rock Flat, about 10km east of Cooma, when it veered from the road about 12.10pm.
The Toyota Hilux rolled several times, before coming to rest on its roof.
A 45-year-old man from Symonston was killed instantly, while a 40-year-old Queanbeyan woman died at the scene a short time later.
Queanbeyan Police say it will be extremely difficult to pinpoint why the ute left the road, given both occupants are now dead.
Speed has been ruled out, and the road was not wet or slippery, according to police.
But Inspector Tony Hill told The Canberra Times that police were currently looking at the possibility that fatigue played a part in the double fatality.
That has prompted warnings from Inspector Hill, who urged drivers to ensure they are rested before taking long trips over the holiday period.
There were a number of witnesses who saw the ute leave the road.
The crash was the second fatal crash in the ACT's surrounds in as many days, and continues a series of horror crashes along the Monaro Highway this year.