BORDEAUX, France: Officials warned on Thursday that flare-ups could cause a massive wildfire to further spread in France’s parched southwest, where fresh blazes have already blackened swathes of land this week.

French Prime Minister Elisabeth Borne will meet with authorities battling the Landiras blaze, south of the city of Bordeaux, and further reinforcements are expected for the 1,100 firefighters on site, the prefecture of the Gironde department said.

“Conditions are particularly difficult: the vegetation and soil are exceptionally dry,” it said in a statement, warning that extreme dry heat was likely to last the weekend. “There is a very serious risk of new outbreaks.”

Temperatures in the region may top 40 Celsius (104 Fahrenheit) on Thursday, weather forecasters predicted.

The wildfire first erupted a month ago in July — the driest month seen in France since 1961 — destroying 14,000 hectares of land and forcing thousands of people to evacuate before it was contained.

But it continued to smolder in the tinder-dry pine forests and peat-rich soil, and officials suspect arson may have played a role in the latest flare-up, which has burned 6,800 ha (17,000 ac) since Tuesday.

“We battled all night to stop the fire from spreading, notably to defend the village of Belin-Beliet,” Lt. Col. Arnaud Mendousse of the Gironde fire and rescue service told journalists in nearby Hostens.

Seventeen homes have been destroyed or damaged since Tuesday, and nearly 10,000 people evacuated, but no further orders to leave the area are expected “for the time being,” Mendousse said.

Acrid smoke has spread across a huge swathe of the Atlantic coast and its beaches that draw huge crowds of tourists each summer, with the Agence Régionale de Santé (Regional Health Agency or ARS) “strongly” urging people to wear protective face masks.

The smoke also forced the closing of the A63 motorway, a major artery toward Spain, between Bordeaux and the city of Bayonne.

France has been buffeted this summer by a record drought that has forced water-use restrictions nationwide, as well as a series of heat waves that many experts say are being driven by climate change.

Currently, there are eight major wildfires raging in several parts of the country, and Interior Minister Gerald Darmanin, who was set to meet with Gironde officials on Thursday, said Sweden and Italy were sending firefighting aircraft to help.