Fierce winds drove heavy rain across large swathes of France on Friday, knocking out electricity for tens of thousands of homes along the western Atlantic coast and causing destructive flooding in the southeast, officials said.

An autumn storm baptised Alex buffeted Brittany overnight, with wind gusts reaching 186 km/h (115 mph) at Belle-Ile-en-Mer, an island off the coast near Nantes.

Huge waves pummelled the shore in Nice, southeast France, on Friday, prompting authorities to close off access.
Huge waves pummelled the shore in Nice, southeast France, on Friday, prompting authorities to close off access. AFP / Valery HACHE

Emergency services were mobilised to clear fallen trees and downed power lines, though no deaths were reported in the region, authorities said.

But many schools and parks were closed, train services were halted and access to the coasts prohibited.

In the southeast, a road bridge was destroyed as muddy waters churned through a valley near Saint-Martin-Vesubie, north of Nice near the Italian border, Eric Ciotti, an MP for the Alpes-Maritimes region, told AFP.

Winds from the storm dubbed Alex tore off part of a school's roof in Vannes, western France.
Winds from the storm dubbed Alex tore off part of a school's roof in Vannes, western France. AFP / Loic VENANCE

"The service station was washed away, houses were severely damaged, and the stadium and the cemetery have been flooded" after some 235 millimetres (9 inches) of rain was dumped in just a few hours, Ciotti said.

Beaches in Nice and other coastal cities were closed, and authorities asked people to stay at home and refrain from using their cars unless in case of emergency.

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