Police are investigating the discovery of bones near the spot where Durham hiker Esther Dingley went missing last year, according to reports.
A mountain runner raised the alarm at around 2pm on Friday after finding what he believed could be the remains of a body.
Spanish police went to the area but alerted their French counterparts after discovering the spot was just over the border, The Mirror reports.
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French police have now taken charge of the investigation to try to confirm if they are human bones and who they could belong to if so.
Spanish police sources said they appeared to be human bones.
A Civil Guard source said: “A mountain runner has found what could be human bones just over the French side of the border at Puerto de la Glera.
“He called the Civil Guard who went to the area but after confirming it was on the French side of the border they called the French Gendarmerie who went to the spot and have now taken charge of things.
“They appear to be human remains but it will up to French police now to analyse them.”
Another Spanish source said it appeared “90 per cent certain” they were human remains.
French police confirmed remains had been found at Port de la Glere but said it would take “several days or even weeks” before they were properly analysed and any results obtained.
French police chief Jean Marc Bordinaro said: "We cannot say anything at the moment because the discovery of the bones is too recent and they must be properly analysed.
"We will not have a result for several days and possibly several weeks."
A prosecutor based in Saint-Gaudens is expected to make an official statement if there are any changes to the current situation.
Puerto de la Glera - Port de la Glere in France - is close to the 8,796ft Pico Salvaguardia summit where Oxford graduate Esther, 37, last made contact with her partner Dan Colegate at around 4pm on November 22 last year.
Specialist officers from Spain and France have carried out several searches of the area around the Puerto de la Glera hiking trail.
Esther’s partner claimed in a recent BBC interview he “could no longer agree” with the idea she had suffered an accident.
He said: “The search has been so prolonged and so intense, that as far as I’m concerned the probability of an accident is now less than the probability of a criminal act.”
The couple have been together for almost 19 years, met at Oxford University and lived in Durham before embarking on a camper van journey around Europe six years ago.
Spanish and French police had previously both said they had found no evidence of any foul play.
Spanish police confirmed last month they had resumed their search for Esther after the winter snow thawed.
Sergeant Jorge Lopez Ramos said at the time snow on the French side of the summit near the border was still making it impossible to restart the search there.
He also predicted summer was the “most likely time of the year” officials would get information that could help them determine what had happened to Esther, saying: “That’s when most people are walking in the mountains.
“At the end of the day 1,000 eyes see more than eight, the summer is when more people leave the well-trodden paths for whatever reason and we’ve got a good chance of seeing some change to a situation which at the moment is the same as it was last year when the search was called off.
“The number of hikers in the area starts to increase towards the end of June but July and August are the two months when there is most people.”
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