Two people died in a black Vauxhall Astra died in a single vehicle crash as it was travelling eastbound on the A711 near to Tower Wood, Dumfries, at about 9.50 pm on Sunday April 23.
Extensive enquiries are underway to establish the exact circumstances of the crash which resulted in the death of two people.
Sgt Paul Dodds said: “A full investigation is underway and we have spoken to a number of people as part of our enquiries.
“We previously appealed for the occupants of an estate car to come forward and I would like to thank the occupants of this car for contacting us.
“However, I am keen to speak to all members of the public who were on the A711 that night, whatever their direction of travel.”
Sgt Dodds added: “Were you on the road prior to the incident taking place, perhaps you saw the black Vauxhall Astra travelling eastbound?
“Any information can be significant in an investigation and it’s important we gather as much detail as possible so we can establish the full circumstances of what occurred.”
Anyone with any information is asked to call Road Policing Officers at Dumfries Police Station via 101.