The only survivor of an avalanche on Ben Nevis, that killed three people, has said: “It’s terrible, they’re not here anymore. They will not see their family again.”

Mathieu Biselx, 30, the president of the Sion branch of the Swiss Alpine Club, was speaking from his hospital bed in Glasgow.

He told Le Nouvelliste: “We arrived Sunday evening in Scotland. It was between 12 and 1pm when everything rocked.

"We were not very high and all of a sudden we heard a noise. We turned around and two seconds later, we were swept away by heavy, compact snow. I lost consciousness and when I woke up, only my head and one arm came out of the snow mass.

“I have seriously injured both legs. My back, one shoulder and one arm are affected, but I’ll get out of it. While my friends, fathers. This is a terrible drama.”

The 30-year-old remains in the Queen Elizabeth Hospital in a serious condition after a group of four climbers were swept away by the avalanche on Ben Nevis, UK's highest mountain.

Three men died following the incident in one of Scotland's worst climbing accidents of recent years.

Two of the men who died were French and aged 41 and 32. Another man who died was a Swiss national aged 43

It is understood all the men were members of a group from the city of Sion, the southwestern Swiss region of Valais. 

Details emerged as Lochaber Mountain Rescue Team warned people to "moderate" their behaviour after some chose to question the wisdom of venturing onto Ben Nevis during avalanche hazard warnings after three climbers were killed.

The team said people should "have some respect" for the loved ones of those who died after some responded harshly to their account of the avalanche tragedy.

READ MORE: Two dead and two injured following Ben Nevis avalanche

A wall of snow is said to have collapsed 4000ft down Ben Nevis leaving them no escape on Tuesday afternoon.

The tragedy occurred while the Scottish Avalanche Information Service issued warnings of a high risk of avalanches in the Ben Nevis area which stretches to 6pm on Wednesday.

SAIS say avalanche risk has come from large areas of unstable snow layers on sheltered north, northeast and east aspects above 800m. There was expected to be further issues on south-east aspects.

They said on Tuesday there was "whiteout conditions with poor visibility even at lower elevations" with winds said to be approximated 50 to 60mph "making progress difficult at times".

Further "difficult mountain conditions" were expected on Wednesday.

The four had endured freezing conditions at Number 5 Gully, which is seen as a winter climb at the easier end of the spectrum.

But local climb experts say that it also has a reputation as a "notorious avalanche run" because of its broad upper section which attracts large accumulations of snow.

Just three days ago two people were carried down Ben Nevis at 1pm after another avalanche in the same gully.

The Herald:

The rescue team responded after there were a number of comments were sent to their social media page, amidst tributes to their work, questioning whether it was wise to have even been on Ben Nevis.

Denise Thomas said: "I never understand why people put themselves at risk in bad weather; so sad and so avoidable."

George Rowley added: "They should not have been there because of avalanche warnings."

The LMRT responded saying: "Can everyone please moderate their comments. We do not want to curb your opinions but there is a time and a place to conduct these debates.

"Please have some respect for the deceased, their families and friends. We are very grateful for all the very kind comments about the efforts of all the rescuers. Please, for the time being, keep your comments to respect for the casualties, the volunteers and the professional support teams. Thank you."

One witness said he was outside the Charles Inglis Clark Memorial Hut on Ben Nevis, which provides shelter from the harsh weather when the avalanche cascaded down Number 5 Gully.

"There were huge powder clouds," he said. "Guys at the CIC hut who had attempted a climb earlier, and had aborted because of the conditions weren’t aware of anyone else out climbing today on the Ben," he said in a forum post. "Didn’t suspect anything until the coastguard helicopter started buzzing around."

Inspector Isla Campbell, speaking in Fort William said: "We can confirm that the next of kin of the three people that died have been informed of their deaths.

"Two of the men who died were French and aged 41 and 32. Another man who died was a Swiss national aged 43. The man who was injured a Swiss national was 30 years old and remains in Queen Elizabeth Hospital in a serious condition.

"Our thoughts are with the family and friends of those who were involved in the avalanche at Ben Nevis yesterday.

"Formal identification will take place in due course."