A young climber is being treated for serious injuries after an avalanche on the UK's highest mountain "wiped out" a climbing party, killing three of them.

The group were caught by the river of snow and ice in a gully on Ben Nevis as Storm Gareth blew in with strong winds on Tuesday morning, triggering a huge search and recovery operation in "brutal conditions", a rescuer said.

One of the climbers, who are said to have all been young men, died "pretty instantaneously", while another could not be saved despite receiving CPR for half an hour, Donald Paterson, deputy team leader of Lochaber Mountain Rescue Team (MRT), said.

A third climber died while being taken down the mountain, while the fourth was flown to Queen Elizabeth University Hospital in Glasgow.

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Mr Paterson told the Daily Telegraph: "We did all we possibly could - we had every available person we could get hold of. There were four stretcher parties. We carried the bodies all the way down. It is a terrible tragedy. They just got wiped out by the avalanche.

"It was brutal conditions."

Lochaber MRT said it received a call out from the Scottish Avalanche Information Service, which recorded a "large" avalanche at No 5 Gully at 11.45am.

The team, along with Glencoe MRT and around 29 volunteer mountain rescuers who happened to be training in the area, raced to the scene.

"Conditions were very difficult with very high winds, snow and thunder and lightning which restricted the support the Maritime and Coastguard Agency helicopters could provide despite some excellent flying," Lochaber MRT said.

Police Scotland were also called to the incident and helped coordinate the rescue effort.
Fort William Inspector Isla Campbell said it had been a "challenging operation".

"I want to pass on my thanks to the mountain rescue teams, colleagues at the Maritime & Coastguard Agency and Scottish Ambulance Service for their assistance in extremely difficult conditions.

"I would also like to praise members of the public and staff from the Scottish Avalanche Information Service who were on scene at the time and provided immediate assistance."

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First Minister Nicola Sturgeon said news of the fatalities was "absolutely tragic", while Skye, Lochaber and Badenoch MSP Kate Forbes said it was "heartbreaking".

Ben Nevis, near Fort William in the western Highlands, is a popular destination for experienced climbers, attracting 125,000 visitors each year.

Tuesday's incident follows two recent fatal accidents on the mountain, which at 1,345m is the UK's highest.

On New Year's Day, a 21-year-old German woman, who was a student at Bristol University, died after she fell from a ridge she had been climbing with three other people.

She had been hiking on what is known as the "ledge route" when she fell around 500ft.

In December, Patrick Boothroyd, 21, from West Yorkshire, died after falling in the Tower Gully area.