Psatha (Greece) (AFP) - The two-man crew of a firefighting helicopter was killed in a midair collision in Greece Sunday as forces battled multiple wildfires that have devastated swathes of land.

Two hired Bell helicopters collided while battling a wildfire in the Psatha area west of Athens, the fire service said.

“The pilots…were taken unconscious to hospital, where their death was confirmed,” the fire department’s director of communications Vassilis Vathrakogiannis said in a televised address.

Television footage showed one of the helicopters colliding with the underbelly of the other helicopter before exploding and plunging to the ground.

The crew of the second helicopter was successfully rescued.

Hundreds of firefighters were attempting to keep a fire west of Athens from approaching the outskirts of Athens after it scaled a mountain overnight.

The fire department grounded all Bell helicopters in the area pending an investigation, state TV ERT said.

The two dead are a Dane and a Greek, said a statement from Prime Minister Kyriakos Mitsotakis, who had earlier warned of “extremely difficult” days ahead.

The accident raised the death toll from this week’s Greek fires to five, after three firefighters died in Crete and the Peloponnese.

- Flight warnings -

The helicopters had been leased from Australia’s McDermott Aviation, part of a fleet of 15. The company has said it has supported operations in Greece for the past seven years.

Officials had warned for days that violent winds made fire-fighting operations from the air hazardous, and most aircraft had been sidelined until Sunday.

Mitsotakis had earlier said Greece was experiencing “extreme weather conditions” with winds that had reached 100 kilometres (60 miles) an hour.

“When the winds blow with such force, even the dozens of aircraft we have at our disposal cannot operate safely,” he wrote on Facebook.

Vathrakogiannis said 220 forest and agricultural fires had broken out around the country since Monday.

Until then, Greece had been relatively spared from heat waves and major fires this summer, unlike France and Spain.

- ‘Most difficult days’ -

“We are perhaps going through the most difficult days of the summer,” Vathrakogiannis said.

A 44-year-old man was arrested Sunday on suspicion of deliberately starting a fire on the Ionian island of Cephalonia, according to the Greek news agency ANA.

Two other men working for an electricity company were arrested over a massive fire near the Porto Germeno coastal village on the Gulf of Corinth, which was apparently started by a power cable spark on Friday.

The National Observatory’s climate tracker meteo.gr said early estimates indicated that over 6,500 hectares (16,000 acres) had been burned in separate fires on the Gulf of Corinth which also swept Porto Germeno.

It added that meteorological conditions remained adverse “mainly due to strong northerly winds, which, however, have partially weakened compared to previous days”.

Porto Germeno and other villages were evacuated when the fire broke out on Friday but local authorities say scores of homes were damaged or destroyed.

Many left pets behind, with municipal crews and volunteers on Sunday rescuing dozens of dogs and leaving food for any cats that could not be caught.

“We could not believe what we were seeing, the fire spread extremely rapidly,” Nikos Georgopoulos from the laboratory of forest management at the Aristotle University of Thessaloniki, told state TV channel ERT.

- ‘Megafire’ -

Earlier this week, fires on the islands of Crete and Paros affected another 6,000 hectares according to meteo.gr.

Theodore Giannaros, a wildfire meteorologist and senior researcher at the National Observatory, said the fires around Porto Germeno appeared to have affected an area of over 10,000 hectares – almost double the original estimate.

“It is highly likely (if not almost certain) that this particular wildfire will be classified as a megafire,” Giannaros wrote on Facebook.

Greece’s Civil Protection Minister Evangelos Tournas on Saturday said the fire department had been “pushed to its limits”.

Gale-force winds created “extremely difficult conditions resulting in many cases where aircraft either cannot draw water or cannot carry out drops due to extreme turbulence”, Tournas said.

The greater Athens area and nearby Voiotia and the island of Evia are under near maximum fire risk on Monday for a second straight day, the civil protection ministry said.