Police looking for missing Bristol landscape architect Joanna Yeates have sealed off an area near a golf course after the body of a woman was found.
Officers closed Longwood Lane in Failand, North Somerset, after the discovery was made by a couple walking their dogs on Christmas morning.
Police said Miss Yeates' parents were aware and were "very very distressed".
She was last seen on 17 December, when she is thought to have returned to the flat she shared with her boyfriend.
Specialist fire crews have now been called to the road where the snow-covered body of a young woman was found on Saturday morning.
In a delicate operation that could take all day, investigators are trying to retrieve the body - which has not been identified - without damaging any evidence at the scene, said BBC reporter Richard Greenaway.
Miss Yeates' boyfriend Greg Reardon, 27, reported her missing to police on Sunday when he returned from a weekend visiting family in Sheffield.
Her keys, mobile phone, purse and coat had been left behind at their flat.
Police had released footage of Miss Yeates buying a pizza at a Tesco Express near her Clifton home on 17 December, the night she was last seen, which they believed could provide a vital clue.
It is thought she went home, but no trace has been found of the pizza or its wrapping.
Her parents, from Hampshire, had earlier said they believed the 25-year-old was abducted.
The discovery of a body, in a roadside verge, was made at 0900 GMT on Saturday, said police.
Ch Supt Jon Stratford said: "I can confirm that Joanna Yeates' parents have been informed of this development. They are naturally very, very distressed. Our thoughts are with them at this very, very difficult time."
An Avon and Somerset Police spokesman added that the area had been cordoned off and Longwood Lane closed at both ends while investigators examined the crime scene.
"A pathologist will be attending the scene to examine the body. It is far too early to confirm the cause of death or any circumstances," he added.
A post-mortem examination is due to take place on Boxing Day, police said.
Our reporter added that six scenes of crime officers were examining the road, which is near Long Ashton Golf Club, on the edge of Bristol.
Altogether about six police cars and 15 officers were at the scene, which was not far from Avon Gorge where officers had been searching for Miss Yeates earlier in the week, he said.
Some 30 detectives have been working full time on the investigation and are being assisted by another 40 staff, including uniformed officers, forensic experts and search teams.
On Christmas Eve churchgoers in Bristol were praying for the safe return of Miss Yeates, who was remembered during midnight mass at Christ Church in Clifton.
Her brother Chris had been handing out leaflets and putting up posters around Bristol in the hope of someone coming forward with new information. Speaking on Friday he said the family was "in complete despair".
Earlier in the week his parents made an emotional TV appeal for their daughter's return.
Mr Yeates said: "She had so much life in her. If it turns out she isn't (alive) I still want her back. We still want to hold her one last time."