A number of others were reported missing after torrential rain hit the mountains above the Cote D'Azur region on Tuesday.

A number of towns in the department of Var were affected, with hundreds of homes flooded.

In Draguignan, a local official said 30cm (11.9in) had fallen since late on Tuesday afternoon.

Water levels were said to be falling slightly in Draguignan on Wednesday, though the rain was continuing in nearby Roquebrune and Frejus.

"We haven't seen anything like this in a decade," said Hugues Parant, the top official for the department of Var.

At least 1,000 people had to leave their homes and spend the night in schools or other temporary shelters, and some 175,000 houses were estimated to have been left without electricity.

Some reportedly sought shelter on the roofs of their homes, while helicopters were brought in to rescue people.

The force of the water swept empty cars and other vehicles down streets in Draguignan.

"This morning, we woke up to find a town centre that was devastated, extremely battered with overturned cars floating in the streets, collapsed roads and gutted houses," said Corinne Orzechowski, the official leading the emergency operation.

Rail and air services in the region were interrupted, and about 300 passengers travelling on a high-speed train between Nice and Lille had been trapped by the flood waters, the AFP news agency reported.

President Nicolas Sarkozy offered condolences to the families of the victims, and pledged his support to rescue workers "mobilising non-stop to provide aid and find those still missing".