In one incident, two French off-piste skiers died after being buried by an avalanche at Val-d'Isere, the resort's tourism office said. The two men were buried under 2.5 metres of snow.

Members of their group had raised the alarm, but rescuers were unable to revive them after finally reaching them, said a statement.

Around 60 kilometres (37 miles) away, another avalanche caught two off-piste skiers in the Areches-Beaufort resort, a local official told AFP.

One of the skiers could not be revived, while the second was taken to hospital with serious head injuries, said regional official Jean-Pierre Mirabail.

French weather forecasters had warned of a high risk of avalanches this weekend, with a level four out of five on the European avalanche danger scale.

The two skiers who died at Val-d'Isere were not equipped with avalanche transceivers and could only be located thanks to their mobile phones.

Rescuers had to probe the snowpack to find them in an area measuring 10 by 15 metres, said the tourist office.