A group of 28 were caught in an avalanche when scaling Mont Maudit – a 4,465 metre peak of the Mont Blanc range near the ski resort of Chamonix – in the early hours of Thursday morning.
While eight escaped with injuries, including severe snow blindness, it has been confirmed that nine were killed. Of these, three were Germans, two Swiss and two were Spanish. British media reports suggested five of the missing were from the UK.
Eye witnesses who saw the avalanche called the French mountain rescue service at 5:50 am, regional French newspaper Le Dauphine reported on Thursday.
French authorities deployed two helicopters and dozens of policemen to hunt for and rescue those caught up in the snow.
Officials told Le Dauphine they feared up several people were still buried.
The paper added that six hours after the accident, chances of recovering anyone alive were rapidly decreasing.