Detectives have been working with military intelligence specialists as searches continue for the bodies of a mother and son murdered almost 50 years ago.
Renee MacRae, 36, and her son Andrew, three, disappeared on November 12, 1976 but their remains have never been found.
In 2022, William MacDowell was convicted of murdering them in November 1976, but he died aged 81 just months later and never disclosed the location of their bodies.
A number of sites near Nairnside, east of Inverness, have been surveyed since Monday, with military experts using drones and light detection and ranging (LiDAR) equipment to carry out the work.
Police said the results will be studied to assess whether further search activity is needed.
Detective Superintendent Brian Geddes said: “This case will never be considered resolved until we find Renee and Andrew. We owe it to the family and friends to make every effort to recover Renee and Andrew’s bodies to provide them with the dignity they deserve.
“The results of this scoping activity will be studied to assess whether further search activity is required.
“I want to thank our military colleagues who have assisted and provided their expertise to this survey, and also the landowners for their assistance with access through the week.
“Our work continues as we try to ensure the family get the answers they deserve. I would urge anyone who may be able to assist, no matter how small you may feel your information is, to come forward and speak to police.”
Mrs MacRae, 36, and her son left their home in Inverness on November 12, 1976.
The car owned by Mrs MacRae – with whom MacDowell was having an affair – was found later that day on fire in a lay-by near Dalmagarry.
Members of the National Centre for Geospatial Intelligence, part of Military Intelligence Services, carried out the survey work this week.
Armed Forces minister Al Carns said: “Our world-class professionals have once again shown how the Armed Forces can bring real value to supporting their civilian partners at home in the UK.
“I want to congratulate our specialists from the National Centre for Geospatial Intelligence on a successful operation to support Police Scotland’s search for Renee and Andrew MacRae.
“This shows our whole-of-society approach in action, and we will continue to support Police Scotland in any way we can.”
