Police investigating the disappearance of Natalie Hemming are speaking to Cambridgeshire officers about a human head that has been found at a quarry 50 miles away.
While local detectives are not actively linking the two investigations, they say they are keeping an “open mind”.
The body part found yesterday afternoon at the quarry near Ely has not yet been officially identified as male or female.
Officers said the head had come from a site owned by Network Rail in Sharnbrook, Bedforshire, which is more than 40 miles away from the quarry and 20 miles away from Milton Keynes.
It is not yet clear how it got from the building site to the quarry, but it is believed it may have been transported in landfill.
Mum-of-three Natlie, 31, lived in Newton Leys, which is next to the massive Bletchley landfill site.
A quarry worker, who asked not to be named, claimed his colleague spotted the head lying on top of a skip and believed it to belong to a woman in her 30s or 40s.
He said: “My colleague collected the skip where he saw nothing out of the ordinary, and put a cover over the top to stop anything falling out during transit.”
“When he got back to our site, he took the cover off and spotted something straight away.
“He said, ‘what on earth is that’, and his first thought was that it was a manikin’s head.
“But then he realised it had eyebrows and hair, and suddenly clicked that it was actually a woman’s head.
“He described the features of the head looking female and said she looked in her 30s or 40s, but he couldn’t be 100 per cent.
“He thought she had dark hair but it could have been dirty blond and just covered in so much muck.
“He called the managers and it was all passed over to the powers that be.”
The man described how the Mick George site is used for waste disposal and said earthy materials are transported in and out of the site to and from locations right around the UK.
Specialist forensic teams are today searching Network Rail land at Sharnbrook, where a rail project is currently taking place and a JCB digger can be seen searching a landfill site beneath the village’s historic viaduct.
Tests are currently being carried out on the body part as police search for clues as to how it came to be found at the quarry in Mepal.
No other body parts have been found by police, who have now launched a public appeal for any information.
A spokesman for police leading the Natalie Hemming investigation said: “ We are speaking with Cambridgeshire Police. We are not currently linking the two investigations but are keeping an open mind.”
Natalie was last seen on May 1. Her partner, 42-year-old Paul Hemming, was arrested three days later and has since been charged with murder.
Despite extensive searches in Milton Keynes, and even at a disused RAF base near Whipsnade Zoo, Natalie’s body has never been found.