Four climbers who died in an avalanche fell around 1,000 feet and ended up buried under up to two metres of snow, the man who led their rescue attempt said today.
Andy Nelson, deputy head of Glencoe Mountain Rescue, said being caught in an avalanche was "a brutal experience".
The two men and two women were found dead yesterday after the accident on Bidean Nam Bian, a mountain near Glencoe in Scottish Highlands.
They were among a party of six. One man escaped using his ice axe but a 24-year-old woman from the Durham area is in a critical condition.
Mr Nelson, who co-ordinated the rescue, said: "Being in an avalanche is literally like standing on a carpet and having it pulled out from underneath you. Any thoughts of trying to swim out from out of it is futile.
"You are on steep ground, essentially standing on a raft of snow that is sliding downhill at speeds of maybe 40mph to 50mph.
"It would have unfolded in a split second, they would have felt the snow moving and then they would have been travelling at a speed that was impossible to stop.
"The man that survived was standing above the snow and we think he actually jumped and got his ice axe into firmer snow.
"They slid over some very rocky ground and ended up about 1,000 feet below, under between 1.5 and two metres of snow.
"It's a brutal experience. There are enormous forces at work and you are being twisted about at high speed."
It is believed the party were descending from a peak on the south side of the valley when the snow-covered slope they were crossing broke away, engulfing five of them and sending them hundreds of feet down the mountain.
All of the missing climbers were found within four hours of the alarm being raised.
The woman has been moved to the Southern General in Glasgow and remains in a critical condition, Northern Constabulary said. Members of her family are with her.
The next of kin of those who died have been told and their names are expected to be released later, it added.
Superintendent Philip MacRae said: "Our thoughts are with the families and all those who are affected by this tragic incident. Members of the climbing party were from different parts of the UK and a priority for us has been to trace and inform all next of kin. They have now been informed and we have family liaison officers in place."
Jonathan Hart, chairman of the Mountain Rescue Committee of Scotland, said: "This was a tragic event and I speak on behalf of all the mountain rescue team members involved when I say our hearts go out to the casualties and the families of all those involved.
"People come from all over the UK and the world to experience and enjoy the mountain scenery and sports in this part of Scotland. Mountain rescue teams train for these kind of incidents and indeed there was a national Scottish Mountain Rescue course on this weekend on avalanche rescue, taking place in the Nevis range.
He added: "Everything possible was done, as part of an outstanding multi-agency response, to increase the opportunities for survival of the casualties and take them off the mountain before the hours of darkness. It is very sad that there has been such a tragic outcome."
The Rev Moira Herkes, who led a service at St Munda's Church in nearby Ballachulish, said prayers for those who had died.
She told the congregation: "We include in our prayers thoughts for the deceased in yesterday's tragic accident on the mountain and their families.
"Somehow life must continue. We accept the challenges of nature as part of our living."
She added: "We also pray for the people who are injured, both physically and emotionally.
"And we give our thanks to those prepared to risk their lives in the saving of others, and do so with a sense of commitment and through thinking beyond themselves."
Scotland's First Minister Alex Salmond has called it "an appalling tragedy", saying "to lose four people from a party of six is truly devastating".
He thanked the police and mountain rescue teams, adding: "Our immediate thoughts and prayers are with the families of those who have been lost."
Police are expected to interview the surviving man today to find out exactly what happened.
Bidean Nam Bian is a munro - a mountain with a height in excess of 3,000ft - with a number of different climbs.