An 18‑year‑old volunteer firefighter has been placed under formal investigation in France after officials suspect him of starting the massive forest fire that devastated the Fontainebleau park south of Paris.

Investigators say the blaze has burned more than 2,000 hectares—about 5,000 acres—and forced the evacuation of roughly 1,000 people. While the fire has been contained, it remains in the process of being extinguished.

President Emmanuel Macron appeared on site and warned that there would be no leniency for arsonists. He noted that the current heatwave, which has seen Europe heat up twice as fast as the global average, has contributed to an unprecedented number of fires across the continent.

The firefighter originally confessed to lighting a lighter and petrol on twigs but later retracted the statement. A second 18‑year‑old man has also been brought under formal investigation, a procedural step that may lead to charges and a court trial.

The Fontainebleau forest is a UNESCO World Heritage site that surrounds the historic Palace and Park of Fontainebleau. Its loss places pressure on France’s firefighting resources, especially as more wide‑scale blazes occur during the summer.

Climatologists point to rising temperatures and prolonged dry periods as key drivers behind the surge in wildfires. France has recorded nearly 11,000 fires since the start of the year, a figure that has spiked in the latest months.