The first European plane arrived on the Mediterranean island of Corsica from Genoa, bringing the number of planes mobilised to 19, along with 4,000 firefighters and soldiers, the Interior Ministry announced in a tweet.
At least 12 firefighters have been injured and 15 police officers affected by smoke inhalation since Monday.
Some fires had been brought under control while others continues to rage on Wednesday morning:
Evacuees on the beach at Bormes-les-Mimosa
Bormes-les-Mimosas: A fire that broke out on Tuesday ravaged 800 hectares near the town in Provence. About 12,000 were moved out of danger, 3,000 of them from campsites, according to France-Info radio. Fire also flared up again between Bormes and La Londe-les-Maures. About 800 firefighters were mobilised, two tracker waterbombers were flying over the area and two Canadairs were to arrive during the morning. Two houses have been burnt and a police officer injured.
La Croix-Valmer: "It's a disaster area, there's nothing left," La Croix-Valmer's deputy mayor, René Caradante reported. The fires near the jet-set resort of Saint-Tropez have been "contained", according to France Bleu Provence radio. Around 80 kilometres inland, 300 hectares of pines and oaks went up in smoke near the village of Saint-Maximin-la-Sainte-Baume. A local official accused the authorities of failing to regularly remove dry undergrowth, making the forest a fire hazard. Seven firefighters were injured at La Croix-Valmer and two at Artigues.
Luberon: Fires were contained in the south of the Luberon, also in Provence, after destroying 800 hectares of forest and scrub. Five firefighters were injured, two of them suffering serious burns to the face and hands, according the Interior Ministry.
Alpes-Maritimes: Fires at Carros had been brought under control after destroying 80 hectares and leaving what mayor Charles Scibetta described as a "lunar landscape". A firefighter suffered burns to the hand.
Nîmes: A fire destroyed 16 hectares close to the historic city before being brought under control. About 20 residents were moved to safety.
Forest fires rage at Biguglia in Corsica
Corsica: Fires slackened off on Tuesday in the north of Corsica but not before burning 1,800 acres of forest. Firefighters worked to control a wall of flames that threatened homes in the north-eastern town of Biguglia. Interior Minister Gérard Collomb hailed the "courage and professionalism" of the emergency services on a visit to the Mediterranean island. France will buy two Canadair waterbombers in 2018, he announced.
"All of France is mobilised," France's fire service chief Colonel Gregory Allione told France Info, adding that extra firefighters had been drafted in from the north.
Thomas Curt, a director at the Irsea environment and agriculture research institute, told the AFP news agency that a decline in farming in the region since the 1970s has made it more prone to fires.
"Farmland is contracting and the forest is naturally expanding, making the area bushier," he said.