One firefighter was slightly injured and taken to hospital for tests when a World War II-era shell exploded at the scene, emergency services said.

The blaze near the town of Luceram has consumed more than 1,600 hectares (4,000 acres) of pinewood and brush since it broke out a week ago.

Five people were killed last month and thousands evacuated in devastating fires that swept through parts of southern France and the Mediterranean island of Corsica, amid the region's worst drought in a quarter of a century.

Two Russian helicopters and three Canadair planes rushed to Corsica Sunday to help firefighters battle a blaze that destroyed 500 hectares of woodlands near Tolla northeast of the island's main city Ajaccio, emergency workers said.

And a fast-moving fire broke out Sunday in a hard-to-reach steep area in the southern Lozere department near the Cevennes national park, with at least 400 hectares ravaged during the day, firefighters said.

With temperatures stuck in the upper 30s Celsius (high 90s Fahrenheit) and showing no signs of falling until later in the week, France was in its worst heat wave in more than 50 years, helping to feed the forest fires.

The unusually high temperatures has also created dangerous conditions for mountain climbers in the Alps, where authorities warned hikers of the heightened risk of rockslides and urged guides to take extra precautions.

Warning signs have been posted along a key access route to Mont Blanc, western Europe's highest peak. On Saturday, 38 climbers had to be evacuated by from the site by helicopter, as falling rock prevented them from descending.

Experts in the Swiss Alps have already warned that the sun is melting ice at abnormally high altitudes, loosening the structure of the mountainside and contributing to an unusually high death rate among climbers this summer.

TERRA.WIRE