It was the largest loss of life to an avalanche in Glencoe, claiming two men and two women. Three climbers died in an avalanche in Glencoe in 2008.
Today's accident involved a party of three men and three women, climbing on Bidean Nam Bian.
They were descending near Church Door Buttress and had just left the ridge when the whole slope collapsed.
One man jumped clear, but the other five were swept down the 3500ft mountain.
The man followed them down and found a woman on the surface with a bad head injury.
He then carried on down until he got a mobile phone signal and called for help.
Glencoe Mountain Rescue Team went to the scene with the search and rescue helicopter from Prestwick, which took the woman to Belford Hospital, Fort William. She is in a serious condition.
John Grieve, leader of the Glencoe team, said the alarm was initially raised by two climbers - who were not part of the group of six - when they discovered one of the casualties lying in the snow.
But, soon after, police were contacted by the male survivor from the climbing party, who told them more people were missing.
Mr Grieve, who is in Spain and was not part of the search, said: "The first call to police was from two other people who had been on the mountain, they found someone lying next to where they were climbing.
"So, the assumption was that it was just one casualty, but it became clear that there were others missing when they heard from the man who is safe."
He said the deceased climbers were located using a technique called "probing", where a metal stick is pushed into the snow.
"I'm not sure how deeply buried they were, but using that technique would suggest it was more than a metre," Mr Grieve said.
All of the missing climbers were located within four hours of the alarm being raised.
Police said they are making efforts to identify the deceased and to contact their next of kin.
Tonight, tributes began to pour in over the "devastating" natural disaster.
First Minister Alex Salmond said: "This is an appalling tragedy and our immediate thoughts and prayers are with the families of those who have been lost.
"To lose four people from a party of six is truly devastating.
"The Scottish Government will provide any support that we can and I would like to thank the police and mountain rescue team for their efforts in these difficult circumstances."
Mr Salmond's deputy, Nicola Sturgeon, posted on Twitter: "Dreadful news from Glencoe. Thoughts with all those affected."
David Gibson, chief officer and company secretary of the Mountaineering Council of Scotland (MCoS): "This was a significant tragedy.
"The thoughts of the MCoS are with all of those involved and the rescue services up there doing the job they do.
"It is always difficult in these circumstances, but I think the advice we would give to people is to check the weather and avalanche forecasts before setting off, and to assess the risks."
Mr Gibson said Bidean Nam Bian is a mountain with a number of different climbs.
"It is a fantastic location to go climbing at this time of the year as it is very beautiful," he said.
Mark Diggins, co-ordinator of the Scottish Avalanche Information Service, said the weather conditions were fairly dry with little snow over the last four days.
He said today's avalanche risk was deemed "considerable", second lowest on a European four-point scale.
The most serious is "very high", which is extremely rare in Britain.
"An avalanche is possible to be triggered by a single person," said Mr Diggins. "At the moment it doesn't look like there's much snow, it is very localised.
"You're really getting into areas which are 800 metres up because the wind packs the snow to make it hard."