The BBC's Andrew Cassell: "The avalanche risk was considered as medium to high"

Three people who survived the tragedy despite lying buried in more than three feet of snow for up to 16 hours have also been named.

Emma Ray, 29, and Paul Hopkins, 28, both from Wilmington in Kent, Matthew Lewis, 28, from Dartford in Kent, and Ian Edwards, 30, for whom no address was supplied, were killed by an avalanche that struck as their group rested 3,500ft up Aonach Mor.

Scottish climber Cameron McNeish: "Tremendous work in absolutely vile conditions"

They were members of a party of six climbers who had been taking part in a basic winter skills course led by "extremely experienced" local instructor Roger Wilde, who survived.

Steven Newton, 24, of Dartford in Kent and Sarah Finch, 25, of Hartley in Kent, were also dug out alive. All three survivors escaped with hypothermia, sprains and bruises and are recovering at Fort William's Belford Hospital.

Sarah's brother David Finch said the group were all leaders in the Dartford branch of the Venture Scouts and had known each other "for years".

Consultant surgeon David Sedgewick said: "They are all very lucky to have escaped with such minor injuries. I would have expected them to have sustained major skull, chest and abdominal injuries."

The accident took place at approximately 1030 GMT on Tuesday, but the group was not reported missing until 2130 GMT when the instructor, Mr Wilde of the Mountaincraft climbing organisation, failed to return.

The first survivor was found between 0100 and 0200 GMT on Wednesday morning.

Lochaber Mountain Rescue spokesman Terry Confield said that it was the first time he had witnessed anyone survive an avalanche in 35 years as a rescuer.

Police spokesman Chas Ross describes the condition of the victims

"Roger [Wilde] had left details of where he was going and we headed straight for that area," he said.

"Within about an hour we had located one of the survivors who was stuck in the snow with the upper part of their body exposed.

"If he hadn't been so easily visible we would have had a massive job on our hands."

Mr Wilde was said to have followed "good mountain procedure" prior to the tragedy and was a member of the mountain rescue team that found him.

'White hell'

Rescuers believe the buried survivors were kept alive by accidentally or deliberately created air holes.

Experienced Scottish climber Cameron McNeish described how the victims would have been trapped in snow that "sets like concrete".

He said: "It certainly wasn't an easy rescue, because conditions have been horrific. You hear people quite often talk about a 'white hell' and I believe that's what it's been like."

The four bodies and three survivors were brought down amid high winds and the threat of further avalanches. The rescue operation was hampered further by the inaccessibility of the area where the avalanche occured.

Up to 35 people were involved in the rescue attempt. Mountain rescue teams from RAF Leeming, Leuchars, Kinloss and Lochaber took part in the search, although at one point helicopters were grounded by winds gusting at up to 50mph.