French officials rushed two firefighting planes to the Paris region on Sunday after a “very virulent” fire of “exceptional scale” erupted in the sprawling Fontainebleau forest about 60km (40 miles) south-east of the capital.

The fire began late afternoon in the one-time royal hunting preserve that today is dotted with quiet villages. It raced across 800 hectares (2,000 acres) and was still spreading early on Monday, officials said, causing the partial closure of the A6 highway, the country’s main north-south artery, and disrupting traffic during a busy, heatwave-stricken summer travel weekend.

High-speed rail was also disrupted. French rail company SNCF said on Sunday evening there were delays of up to six hours for trains arriving at or leaving from Paris’s Gare de Lyon.

Firefighting aircraft had to suspend operations at nightfall on Sunday. About 15 homes were evacuated in the village of Vaudoue and firefighters were defending several other towns in the area, said the local Seine-et-Marne fire service.

Without the firefighting planes, other villages would already have been evacuated, said Olivier Compta, who was overseeing the firefighting operation.

About 400 firefighters worked to contain the fire, which erupted two days before the 14 July Bastille day national holiday.

Eric Brocardi, of France’s national federation of firefighters, said it was the first time firebomber planes had been sent up from the normally drier and hotter south of the country to extinguish fires in the Paris region.

Two firefighting helicopters and an observation aircraft were also helping to fight the blaze, he added. “The aim is to save lives and property,” he said as the fire advanced.

Earlier, firefighters dealt with a fire that had blocked a highway running east from Paris and disrupted a high-speed train line to the south of France.

The Paris region – and large parts of the rest of France – have been sharing in a succession of heatwaves since May that have seen temperature records broken in several countries across Europe and have caused thousands of excess deaths, according to estimates in Belgium, Britain, France and Spain. Several other European countries have faced record-breaking average temperatures.

The June heatwaves would have been “virtually impossible” without climate change, the World Weather Attribution group of scientists said.

The interior minister Laurent Nunez, whose office announced he would visit Fontainebleau on Monday, said that forest fires had already consumed 17,000 hectares this year. Once the figures had all been tallied, that would come to 25,000 hectares – “twice as much as the same period” in 2025, he added.

With Agence France-Presse