Missing British hiker Esther Dingley is more likely to have 'lost her way and fallen off a mountain in the Pyrenees than have been victim of a criminal act', according to rescue expert

Missing British hiker Esther Dingley is more likely to be the victim of a tragic accident than a criminal act, claims a leading mountain rescue expert.

Esther's boyfriend Dan Colegate recently suggested – before human remains were found near where the Oxford graduate disappeared in the Pyrenees last November – that he increasingly feared foul play.

But speaking after the discovery of what is believed to be a human skull and hair in the area last week, mountain rescue guide Patrick Lagleize said he believed it likely that Esther had lost her way and fallen to her death on treacherous scree loose rock and .

French forensic experts are now testing the remains with DNA samples from Esther's mother Ria, and also checking Esther's dental records for a match.

Mr Lagleize, President of the Pyrenean Guides Association said: 'You can lose the way and slide on the scree. Logically, for Esther to have fallen that way, is unfortunately quite plausible.'

He added a note of caution: 'We must be careful and await the DNA analysis.'

Missing British hiker Esther Dingley is more likely to be the victim of a tragic accident than a criminal act, claims a leading mountain rescue expert

But speaking after the discovery of what is believed to be a human skull and hair in the area last week, mountain rescue guide Patrick Lagleize said he believed it likely that Esther had lost her way and fallen to her death on treacherous scree loose rock and

There was a major breakthrough on Friday when a skull with long hair was found close to Port de la Glere, a mountain pass on France's border with Spain, just south of Bagneres-de-Luchon. The trail is known as Puerto de la Glera in Spanish 

Esther's boyfriend Dan Colegate recently suggested – before human remains were found near where the Oxford graduate disappeared in the Pyrenees last November – that he increasingly feared foul play 

Mr Lagleize knows only too well the hazards associated with the Port de la Glère near the French-Spanish border, where Esther, 37, was last sighted.

The Port or is four miles long and rises and falls 2,000ft reaching a maximum altitude of 7,794ft and is rated as moderately difficult.

It is believed possible the skull – which Spanish police believe they are 90 per cent sure is human -- may have been moved by a wild animal from elsewhere, as extensive searches over the last few weeks produced no sign of Durham-born Esther.

Mr Lagleize cited an earlier case of young missing French climber Gatien Loison, 32, whose skeleton was found nearby in 2012, three years after his disappearance.

'When there is a disappearance in the mountains and the victim cannot be found, then it is because we cannot match them with their planned itinerary.

'It is then necessary to count on luck to find traces of the person, often several months, even several years later.

'We cannot find the victims in the mountains if we do not understand the logic of their path.

'I am thinking of the disappearance of Gatien Loison. The guy was a seasoned hiker, but not a mountaineer. However, he fell while trying to climb out. It didn't make any sense. Hence the difficulty in finding him. After that, unfortunately, you have to rely on luck.'

Ms Dingley  (pictured right with her boyfriend Daniel Colegate) went missing on November 22 

Two hikers raised the alarm after discovering what he believed could be the remains of a body near the spot where missing hiker Esther Dingley went missing late last year

 Specialist officers from Spain and France have carried out several searches of the area around the Puerto de la Glera hiking trail, where Esther was hiking before she went missing

Even without an unplanned diversion, Mr Lagleize told French website LaDepeche.fr that the Port de la Glère has more than its share of dangers which can prove lethal for travellers.

He said that as a former member of the Gendarmerie's elite rescue unit, the 'High Mountain Platoon' he was once called out to rescue some people who were stranded on a rocky ridge and a mis-step of a few cm would have been extremely serious.

'We had also been called for another person who had fallen. There, the outcome was much less favourable.

Meanwhile, the wait goes on for Esther's mother and boyfriend, who are believed to have based themselves in France until they receive confirmation or otherwise that the remains are Esther's.

Mr Colegate, 38, claimed in a recent interview he 'could no longer agree' with the idea she had suffered an accident.

He told the BBC: '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.'

Nearly eight months after Esther's disappearance, her Fiat Chausson motorhome is still impounded at the Guardia Civil local HQ in Benasque, from where her ill-fated journey began.