BBC Correspondent Damian Grammaticus: Conditions have been described as "horrendous"

The party of six climbers - all in their twenties and from Kent - had been taking part in a basic winter skills course led by an "extremely experienced" local instructor.

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

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

The first survivor was found between 0100 and 0200 GMT on Wednesday morning. Only Mr Wilde, who survived the avalanche, has so far been named.

Lochaber Mountain Rescue spokesman Terry Confield described the discovery of the missing party.

"This person above the snow was found and the digging process began. The people were in a close bunch with rucksacks and ropes together. You've got to be very careful you don't cause any further damage," he said.

Experienced Scottish climber Cameron McNeish, who was walking in the area on Tuesday, 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 bodies and the 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. Inverness ambulance service said a ski lift was used to bring the survivors down one at a time.

Aberdeen Mountain Rescue spokesman Alan Crichton said it was fortunate that anyone had survived, adding "I think somebody's been looking after them".

Police spokesman Chas Ross describes the condition of the victims

"The quarry we're speaking about is on the east face of Aonach Mor. The foot of the quarry is 1000m and the cliffs up above it are another 500ft above that.

"It's a fairly arduous trek just to get into it," he said.

The survivors - who are described as hypothermic - have been taken to Belford Hospital, Fort William.

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 up to 50mph.