French and Italian rescue services have stepped up their search efforts after floods cut off several villages in the mountainous border regions, causing widespread damage and killing three people.
Eight people remained unaccounted for on the French side of the border after storms, torrential rain and flash floods battered the area, washing away roads and houses, cutting off entire villages and triggering landslips.
In Breil-sur-Roya, a French village close to the Italian border, houses were buried in mud and turned-over cars stuck in the riverbed.
Rescue efforts were concentrated on the Roya valley where roughly 1,000 firefighters, backed by helicopters and the army resumed their search for survivors and helped people whose homes were destroyed or inaccessible.
Storm Alex barrelled into France's west coast on Thursday bringing powerful winds and rain across the country before moving into northern Italy.
"What we are going through is extraordinary," said Bernard Gonzalez, prefect of the Alpes-Maritimes region, after as much as 60cm of rain fell in 24 hours in the worst-affected areas.
Italy confirmed two people died yesterday, a volunteer firefighter on a rescue operation and a man whose car was washed away.
France suffered its first fatality today - a shepherd whose body was pulled from a river near the border.
France has declared the region a natural disaster zone.
Saint-Martin-Vesubie, a French village home to 1,400 north of Nice, was completely cut off by the storm.
A bedraggled group of tourists and residents gathered in the village square to be airlifted to safety, an AFPTV journalist said after reaching the site on foot.
"My three-storey house, it's in the river," said villager Sandra Dzidt, 62, who had to flee the floods dressed only in her nightgown.
"All I have left is a tiny piece of wall and a door."
Across the region, emergency crews were handing out food and airlifting thousands of bottles of water into remote villages cut off by the storms.
Helicopter procession'
French Prime Minister Jean Castex inspected the damage by helicopter yesterday, saying he feared the number of people missing could rise after dozens of cars and several houses were swept away in apocalyptic scenes.
Mr Gonzalez called on the families of the missing not to give up hope.
"Just because their loved ones haven't been able to get in touch doesn't mean that they have been taken by the storm," he said.
Many landline and some mobile phone services were disrupted, with some villages using satellite phones to communicate with rescue services.
Despite forecasts of more rain, rescue efforts were to continue throughout the day, Mr Gonzalez said.
"The helicopter procession will continue all day long," he said.
The presidents of Italy's Piedmont and Liguria regions signed a joint letter calling on the government to declare a state of emergency with several villages cut off.
