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 on Wednesday.

More than 6,000 hectares (15,000 acres) of tinder-dry forest have burned in just 24 hours in the so-called Landiras blaze, the largest of several that scorched the region last month.

It had been brought under control but not fully extinguished after burning nearly 14,000 hectares, before flaring up on Tuesday, forcing the evacuation of some 6,000 people.

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

Interior Minister Gerald Darmanin said more than 1,000 firefighters were now battling the blaze, adding that investigators suspected arson may be involved.

“There were eight fires that erupted between 8and 9am that erupted at intervals of a few hundred metres, 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. He also told reporters that Sweden and Italy would send fire-fighting aircraft to France within 24 hours to help.