Firefighters tackle a blaze near Hostens in southwestern France on August 10, 2022. Photo: VCG

A wildfire that officials thought was under control in southwest France has reignited amid a record drought and extreme heat, possibly the result of arson, officials said Wednesday.

More than 6,200 hectares of tinder-dry forest have burned in just 24 hours in the so-called Landiras blaze, the largest of several that scorched the region in July, prompting the evacuation of 10,000 people since Tuesday evening.

It had been brought under control - but not fully extinguished - after burning nearly 14,000 hectares, before flaring up on Tuesday.

The French government said Prime Minister Elisabeth Borne and Interior Minister Gerald Darmanin would travel to the frontline of fire-fighting efforts in the French region of Gironde on Thursday.

Following the reignition of the fires, Darmanin announced more resources including more than 1,000 firefighters, nine planes and two helicopters equipped to drop water.

No one has been injured but 16 homes were destroyed or damaged near the village of ­Belin-Beliet, and officials said six fire engines had been burned.

"The risks are very high" that parched conditions will allow the fire to spread further, said Martin Guespereau, prefect of the Gironde department.

"The weather is very ­unfavorable because of the heat, the dry air, the record drought and the fact that there is a lot of peat in the ground... the fire didn't go out in July, it went underground," he told journalists.

Darmanin said investigators suspected arson may be involved.

"There were eight fires that erupted between 8 and 9 am that erupted at intervals of a few hundred meters, which is extremely unusual," he said in Mostuejouls, north of the Mediterranean city of Montpellier, where another fire was raging in the Grands Causses natural park.

"It's a major fire... much more intense and fast-moving" than at the height of the Landiras blaze in July, Marc Vermeulen of the regional firefighting authority told journalists.

"I opened the door last night and there was a red wall in front of us, the sky was roaring like the ocean," said Eliane, a 43-year-old at a temporary shelter for evacuees in Belin-Beliet.

The fire was spreading toward the A63 motorway, a major artery linking Bordeaux to Spain, with thick smoke forcing the road's closure between Bordeaux and Bayonne.

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

Wildfires have also ignited in the dry hills of the southeast and even in the normally lush areas of Brittany along the coast.