Police investigating the murders of Renee MacRae and her toddler 43 years ago have started draining a flooded quarry in a bid to find their bodies.

Officers believe their remains could be buried in the 100ft Leanach Quarry near Inverness.

Renee MacRae, from Inverness, and her three-year-old son Andrew, disappeared on November 12, 1976.

The 36-year-old's car was found on fire in a lay-by on the A9 south of Inverness later that day.

A team of detectives have been working to "identify new lines of inquiry and develop any existing lines of inquiry".

Now officers are draining the quarry after it was deemed unsafe for divers to go into.

On Monday, Inspector Brian Geddes said: "This is a significant development in the ongoing investigation into the murders of Renee and Andrew MacRae.

"Work is now underway to carry out a forensic search of Leanach Quarry where we believe key pieces of evidence may have been concealed.

"A key part of this operation is to recover the remains of Renee and Andrew if they are within the quarry, and gather evidence vital to this ongoing investigation.

"We are working with a number of different partners on what will be a challenging and complex operation expected to last several weeks. I would also like to thank local landowners for their co-operation in this inquiry."

He added: "The quarry has previously been deemed too dangerous to search using divers, which is why the decision has been made to pump the water completely from the site.

"We will thereafter remove the sediment from the quarry, which will allow specialist search officers and forensic experts to carry out a meticulous search of the material.

"It is a major undertaking for everyone involved but the determination remains within Police Scotland to solve this case and bring closure to Renee and Andrew's family and friends after all these years.

"We intend to do everything we can to ensure that any key pieces of evidence which we believe are in there, are recovered.

"I would also appeal to anyone with information to please come forward and speak to us."