Two firefighting helicopters collided in Greece while helping to control a huge wildfire on Sunday that has destroyed more than 100 homes northwest of Athens, while a fresh blaze forced evacuations on ​the popular tourist island of Kefalonia.

Europe has been ravaged by wildfires this summer after a period of record-breaking heatwaves and little rain – conditions that scientists say have been ‌exacerbated by climate change.

Destructive blazes in France and Spain showed signs of easing over the weekend, but several wildfires have broken out in Greece after a period of relative calm there.

Two helicopters collided during a firefighting operation in the area of Psatha in the Attica region, west of Athens, Greece's fire service said in a statement.

Footage posted on the Forecast Weather Greece Facebook page appeared to show two helicopters closing to cross paths at low altitude, before the main rotor of the lower ​helicopter struck the underside of the one flying above it and crashed in flames. The second helicopter then dumped its load of water and flew away. Reuters has not verified the ​authenticity of the footage.

The crew of one helicopter had been located and were safe, with ambulances on the way to pick them up, government officials said. ⁠As for the second crew, the helicopter had been located, and a search-and-rescue operation was underway, officials said.

'FORCE OF NATURE'

Gale-force winds that had fuelled a fire around Porto Germeno on the Gulf of Corinth 60 ​km (40 miles) northwest of Athens subsided, but flames crossed a mountain to the south and reached the settlement of Veniza and a military firing range, igniting unexploded ordnance. Firefighters focused their efforts on preventing fire from ​advancing towards the coastal town of Megara, which has a population of around 30,000.

"There are moments when the force of nature and the intensity of weather conditions exceed all human planning and every operational capability,” Prime Minister Kyriakos Mitsotakis said in his regular Sunday message.

Greek authorities issued emergency alerts for evacuations for a number of settlements in western Attica, including an industrial estate near Megara.

In the village of Agios Konstantinos, residents were doing their best to halt the spread of the ​blaze.

"The fire has been burning since last night, it is certain that they cannot have forces everywhere. We as residents are doing everything we can,” said Tasos Tzempelikos, 61, who along with his son ​was pouring water on the fire.

Greek daily Protothema reported that a major effort was under way to prevent the fire from Veniza from reaching the nearby coastal town of Megara. It said more than 10,000 hectares of land had ‌likely been ⁠destroyed by the fire so far.

Overnight, several settlements on the Ionian island of Kefalonia were evacuated after a fire broke out in the Pastra area in the south.

FIRES IN FRANCE AND SPAIN MOSTLY UNDER CONTROL

In France, wildfires in the Gironde and Var departments showed signs of easing. Authorities reported only minor flare-ups in the southwestern Gironde area and said the blaze in the southeastern Var department had not spread overnight.

In Monfort-Sur-Argents, in the region of Var, Georges Blanc, who fled from the fire, returned home and was busy putting out hot embers to prevent a flare-up, while firefighters watered the wider area.

"With the combined efforts of the two ​Canadairs (firefighting planes) and the firefighters, I think you could ​say all the houses were saved ... And now, ⁠well, I'm coming back to check, because since I saw the flames, I thought the houses wouldn't have survived," he told Reuters.

In central Spain, wildfires that ripped through tens of thousands of hectares over the past week were mostly under control, though firefighters were dealing with reignitions in some areas.

In the western province ​of Caceres, a forest blaze erupted on Saturday, prompting the evacuation of around 800 people. Those residents were allowed to return on Sunday but remained ​confined to their homes as ⁠the fire was still active.

HUNGARY NUCLEAR PLANT FORCED TO SHUT

Other European countries are struggling with drought and receding water levels in major rivers, including the Rhine and the Danube, which recorded its lowest-ever water levels in Hungary, Serbia and Romania.

Hungary faces a critical five days, Prime Minister Peter Magyar said on Sunday, as the drying out of the Danube forced the country's sole nuclear power plant to shut for the first time in more than four ⁠decades, with a ​new heatwave looming.

Falls in water levels amid a lack of rain have also disrupted shipping and tourism, opens new tab in Hungary and triggered water-use ​restrictions in more than 100 cities and villages.

Danube levels in Serbia fell to their lowest since 1985, cutting the daily output of the country's biggest hydropower plant to only 20%, the energy minister said on Sunday.