Hundreds of people had to be evacuated in southern France after flash flooding turned roads and fields into rivers and lakes.

       No casualties have been reported following the downpours in the Gard region.

       But local authorities said the floods caused significant damage to homes and infrastructure across towns and villages between Nimes and Montpellier.

       As new heavy rainfall threatened the area Wednesday, the emergency service for the Gard region said rescuers were searching for at least one person reported missing on Tuesday evening.

       One person was hit by lightning but survived, and a supermarket roof collapsed under the pounding water, according to the regional emergency service.

       People evacuated from a campground described on BFM television that they watched waters surge toward their campers. About 800 firefighters were mobilised to rescue people via helicopter and other means.

       Schools across the region were closed Wednesday as cleanup work started in some towns.

       The flooding comes after a season of extreme weather that saw devastating wildfires near the French Riviera and around the Mediterranean, record-breaking flooding in Germany and Belgium and droughts or heatwaves in other areas around the world. Scientists say such events are expected but happen more frequently now as the planet is warming because of human-caused climate change.