Five people are feared to have died in France as flash floods swept the south and east of the country, forcing about 3,600 people to evacuate their homes and two nuclear reactors to close down.
"All public services have been mobilised," Environment Minister Roselyne Bachelot, speaking after an emergency cabinet meeting, said of rescue operations involving 4,000 firemen, 100 soldiers and eight helicopters.
"We expect rainfall to reach a peak tonight which could bring flooding to a peak tomorrow," she warned. Earlier authorities advised motorists to avoid using their cars in the worst-hit areas.
Bachelot said 3,600 people had been evacuated from their homes across the region. Rescue services used barges to evacuate 1,000 people from their homes in a northern suburb of Marseille and bring them to shelter in local sports halls.
"We are on a war footing. The situation is extremely worrying the length of the Rhone valley," Christian Fremont, prefect of the Provence-Alpes-Cote d'Azur region.
A spokeswoman for the government nuclear safety authority ASN said the two reactors were shut early on Tuesday as a precaution after the heavy rains. She said the restarting of the reactors would depend on river levels.