Police are shifting through 100,000 tonnes of earth at a quarry in the search for a murdered mum and son.
Renee MacRae and three-year-old Andrew were last seen driving out of Inverness more than 40 years ago.
The 36-year-old mother-of-two’s BMW was found burnt-out in a lay-by on the A9 near Dalmagarry, 12 miles south of the city, but the pair have never been seen since.
Officers have shifted through more than 100,000 tonnes of earth at Leanach Quarry, with 5000 of that being analysed for forensic searching.
Approximately 55 vehicles, which aren’t linked to the murder investigation, have also been uncovered during the excavation phase.
It comes after objects were recovered in June from the quarry including pram wheels, similar to the make of the one used by Mrs MacRae.
Inspector Brian Geddes said officers are confident of finding the mother and son’s remains if they were disposed in the quarry.
He said: “The forensic search of the quarry has been a significant undertaking. We have almost completed the excavation process but there remains a vast quantity of material that still requires to be sifted and thoroughly searched.
“This is likely to take a number of weeks to complete but we are confident that if the remains of Renee and Andrew, or any other key pieces of evidence, were disposed of in the quarry, we will find them.
“The process of backfilling sections of the quarry where excavation has taken place has commenced and again this will continue over a matter of weeks.
“I would like to thank everyone that has been involved in the operation to date, and the surrounding community for their patience while this has been ongoing.
“We remain determined to bring this matter to a successful conclusion and we continue to progress all relevant lines of enquiry.
“I would urge anyone who we have yet to speak to, and who has information, to please come forward and contact us.”
The site was previously deemed too dangerous to use divers but police were “extremely confident that vital evidence” would be found.
Bones were also recovered from the site in June but only animal parts have been identified so far.
In 2004, a full cold case review resulted in a month-long excavation of Dalmagarry Quarry.
Several days were spent at Leanach Quarry last October when officers released an image of young Andrew around the time of what would be his 45th birthday.
A picture of a Silver Cross pram, identical to the one used by Ms MacRae for her son, was also released. It was believed to have been with them when they went missing.
Last year, Police Scotland made a fresh search of a disused quarry near Inverness that had been examined in the days following the pair’s disappearance.
Police issued an appeal for information jointly with Mrs Macrae’s sister Morag Govans during November last year.
She said: “Not a day goes past that both are not in my thoughts.
“Even after the passage of time I believe that there are people who know what happened to Renee and Andrew, and I will never give up hope of getting justice for them both.
“I appeal for anyone with any information to come forward and for others to examine their conscience to end 42 years of pain and anguish to allow us to grieve for Renee and Andrew.”
She added: “Andrew was a mischievous and fun-loving wee boy.
“It is impossible to take in that his life was brought so cruelly to an end at such a young age.
“He would have turned 45 in October and I often wonder what he would have been doing now with the life that he was never given the chance to build.
“Renee was a compassionate and caring mother.
“Both Andrew and his elder brother Gordon were her life. She adored them and was so proud of her boys.
“Gordon was only eight and has lost the love and guidance of his mum and brother.”