MARSEILLE, France (Reuters) -A wildfire burning in the hills behind the French Riviera resort of Saint-Tropez since Monday has killed at least two people, local authorities said on Wednesday.

Some 1,100 firefighters as well as water-bombing aircraft are fighting the blaze that has scorched more than 7,000 hectares of land and forced the evacuation of several thousand people from their homes and campsites.

Firefighters have so far been unable to contain the blaze as a strong ‘mistral’ wind fans the flames across a tinderbox landscape. New fires broke out on several flanks during Wednesday.

Holidaymakers on the Mediterranean coast watched from their sun-loungers as paddleboards as thick plumes of smoke blew across the sky. Police had to shut down one stretch of motorway because of poor visibility.

The blaze broke out in the Plaine de Maures nature reserve, some 50 km from Saint-Tropez. The fire had swept through half of the reserve, causing an irreversible loss to biodiversity, junior government minister Berangere Abba said.

“We have some hope conditions will ease tonight, but there are no guarantees,” local prefect Evence Richard told a news conference.

Two people had been killed and 24 hurt, among them five firemen, he said, adding that it was still too early for those evacuated to return home or to their holiday lodgings.

President Emmanuel Macron on Tuesday left his nearby summer retreat to thank the firefighters for their efforts.

Waves of extreme heat have hit much of the Mediterranean region in recent weeks, with wildfires in Spain, Greece and Turkey raising uncomfortable questions over global warming and countries’ preparedness.

(Reporting by Marc Leras in Marseille and Sudip Kar-Gupta and Richard Lough in Paris; Editing by Tom Hogue, Giles Elgood and Philippa Fletcher)