Italian climber evacuated from K2 mountain

(CNN) -- A Pakistani rescue helicopter evacuated an Italian climber Wednesday -- four days after he survived a deadly ice avalanche on K2, the world's second highest mountain.

The helicopter picked up Marco Confortola and a number of his colleagues from a base camp on the mountain. Confortola was immediately taken to a hospital in the Pakistani town of Skardu.

"He was in good shape, but he could not walk," said Col. Mueen Uddin, a pilot for Askari Aviation, a company that sent the helicopter. "His feet were frostbitten."

Uddin said weather conditions on the mountain were not good initially, but were not a problem when they left the mountain.

The identities and conditions of the other two people were not immediately known, he said.

Confortola survived an ice avalanche on K2 on Saturday that killed 11 people. He arrived at the mountain's base camp Tuesday, where doctors treated him for frostbite on his feet, according to updates of the rescue operation provided by his expedition team's Web site.

Two other survivors, both Dutch men, were flown to a hospital in Skardu, Pakistan, on Monday, a day after making their way down the mountain to K2's base camp. They are also suffering from frostbite. Watch how the climbers were rescued »

Confortola was on his way to that same hospital Wednesday, Mirza said.

The three men were part of a group "stuck up high on the mountain" after an ice avalanche in the early hours of Saturday, team spokesman Michel Schuurman said.

The tragedy struck as the group was on the way down after 17 climbers had reached the summit. It left 11 climbers dead, including a sherpa who had gone up to assist in rescue efforts, according to mountaineers working with the climbers involved.

One of the Dutch survivors, Norit expedition leader Wilco Van Rooijen, was missing after the avalanche and there were concerns that he had not survived. But a blog entry posted on Saturday read "Wilco found alive!" and said his survival "is bound to go down as one of the greatest mountaineering tales in K2's history."

The avalanche struck down the safety ropes that the climbers planned to use to descend the mountain, Schuurman said.

"They had to descend without any safety lines and in that descent we know that some climbers have slipped down and their whereabouts are unknown," he said.

K2, which is near the Pakistan-China border, is considered by many climbers to be more technically challenging than world's tallest peak, Mount Everest. Map of the area »

The site of the accident, about 8 kilometers (5 miles) up the mountain, is what climbers call the "Dead Zone," because the body would never recover if stuck in such freezing conditions with so little oxygen, said Pat Falvey, a climber in Ireland who is in touch with the climbers and posting updates online for one of the climbing expeditions.

While the climbers and rescuers who made it down safely were not immediately in condition to speak publicly, they told Strang and Falvey what had happened.

On Friday, the 17 climbers reached the summit together -- one of the largest groups ever to reach the summit simultaneously -- said Falvey.

The climbers were Dutch, Irish, Italian, French, Norwegian, Korean, and Nepalese citizens

As they were descending, a "moving river of ice broke loose ... like an iceberg breaking loose from a glacier," and it knocked down the fixed rope that the group had been using to move safely from the higher reaches to a camp at a lower altitude, he said.

The rope's collapse knocked down three climbers, sweeping them away in an avalanche of ice and killing them, he said.

"Not only did it wipe away the fixed ropes, but it brought the whole slope into icy, dangerous conditions."

Two climbers managed to make it to base camp, but many of those stranded decided the best course of action was to wait and hope rescuers could put up ropes and make it up, Falvey said.

As time went on and rescuers didn't come, the remaining climbers decided their only chance at survival was to go into the treacherous, icy conditions of the mountain's bottleneck and try to make it through. But as they did, some climbers fell to their deaths.

A few managed to survive, with the help of rescuers, Falvey and Strang told CNN.

It is the deadliest incident on K2 since 1986, when 13 of 27 climbers died after summiting the peak, according to Outside Magazine.

Strang said the tragedy could have been avoided. Too many people were climbing together "at a very slow speed," and should have turned around to begin their descent sooner, he said.

"Coming down at dawn, in the dark, with little oxygen is very, very dangerous," he said.

CNN's Rory Suchet contributed to this report

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