At least eight people are thought to be trapped under the snow. They were among a party of climbers hit by a wall of snow 200m (600ft) long and 50m wide. Eight survived the snowslide and were taken to a hospital in Chamonix. The search for survivors, involving helicopters and rescuers with dogs, has been hindered by new avalanche threats. Officials said the eight missing on the Mont-Blanc du Tacul mountain included five Austrians and two Swiss climbers.