Clouds billow over the French Alps where an avalanche in the mountains swept Thursday nine climbers to their deaths, near Chamonix, France, Friday, July 13, 2012. Three Britons, three Germans, two Spaniards and a Swiss climber were killed, and 14 people were injured in Thursday's accident below the summit of Western Europe's highest peak. A memorial ceremony is scheduled for Saturday afternoon in the Alpine town of Chamonix. (AP Photo/Massimo Pinca)
CHAMONIX, France (AP) — Climbers who survived the massive avalanche in the French Alps that killed nine of their colleagues said Friday they were tossed around by a wave of snow that hit without a sound.
Local officials, meanwhile, insisted it would have been impossible to foresee Thursday's deadly avalanche.
One survivor, Danish climber Thomas Dybro, 30, told The Associated Press that he was deeply shaken by what happened and wouldn't be returning anytime soon to Mont Blanc.
"All of a sudden big pieces of ice fell down right next to us. ... And then a split second after that it all came down and hit us and blew us away," he recalled. "I feel like I've been hit by a truck and did ten rounds (of boxing)."
Three Britons, three Germans, two Spaniards and a Swiss climber were killed and 14 people were injured in the avalanche on one of the most popular routes to the summit of Mont Blanc, western Europe's highest peak at 15,782 feet (4,810 meters).
Daniel Rossetto, a 63-year-old mountain guide, said the avalanche hit silently as he led two Danish climbers up the mountain, tossing them around like a washing machine. Luckily they were on the edge of the massive slide and all three survived.
"Big chunks of snow fell onto us so we were swept. We all fell together. And that's it. It's quick but it's always too long," he told AP. "It's a lot of impact. It's a 40-degree slope, and we fell about 200 to 250 meters (650 to 820 feet)."
Early summer storms had left behind heavy snow but the weather had cleared enough in the past several days to encourage many guided and independent teams of climbers to set out. The avalanche on the north face of Mont Maudit hit two hours after 28 climbers had left a high-altitude climbing hut.
Britain's ambassador to France, Sir Peter Ricketts, said the climbers "were doing nothing imprudent" and there were "no indications of an avalanche" ahead of time.
The area where the wind-slab avalanche occurred typically sees between four and 10 accidents per day this time of year, but rarely something so serious, said Jean-Louis Verdier, the deputy mayor of Chamonix and a mountain guide himself. On busy days, up to 80 people a day can be on that route.
There had been no specific alerts for avalanche risks there, he said, and usually such risks are only detectable when a climber is there to examine the snow firsthand. In this case, he added, it was impossible to detect a weak layer in the snow beforehand because the snow had been compacted by strong winds.
The head of the Chamonix mountain search and rescue service, Jean-Baptiste Estachy, echoed that view.
"You can't predict when it is going to detach and this one wasn't expected and it couldn't have been predicted," he told a news conference in the Alpine town of Chamonix.
He and other authorities say the avalanche at 13,100 feet (4,000 meters) high was caused either by the collapse of a serac — an ice cliff — breaking off above the climbers or by a climber inadvertently setting a slab loose.
At the hospital, Dr. Frederic Champly said seven of the 28 climbers hit by the avalanche survived unscathed.
"One of the climbers who was ahead, by sticking his ice ax in the snow, snapped off the slab that had accumulated for two or three days up there and the slab set off and swept all the rope teams," he said, recounting what the climbers had told him.
But it doesn't matter what caused the avalanche, said British mountain guide Stuart Macdonald, director of the Avalanche Academy in Chamonix.
"In hindsight, what we know is that it was unstable snow," he told AP. "It doesn't matter what triggered the avalanche and we might never find out."
Macdonald said while the slopes of the two peaks along the route leading to Mont Blanc are renowned for their avalanche risk, there had been hardly any snow in Chamonix during the past week. He said photographs of the accident site showed clear evidence of multiple slides across the slope and deep unstable layers within the snowpack.
Yet Macdonald and other guides were still setting out with clients Friday, although poor weather limited many to lower heights.
A memorial was to be held Saturday in Chamonix.
Milos Krivokapic, Philipp-Moritz Jenne and Bastien Inzaurralde contributed to this report.
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