Two aircrew were killed when two firefighting helicopters collided in midair west of Athens on Sunday while working to contain wildfires that have destroyed more than a hundred homes and forced evacuations across Greece.

The two Bell helicopters, leased by the Greek fire department and carrying four crew between them, collided in the Psatha area while tackling a blaze there, the fire service said. Television footage showed one aircraft explode and fall to the ground in flames after what appeared to be a rotor strike. The helicopters had taken off from Elefsina military airport inside the Athens metropolitan area.

A Danish pilot and a Greek crew member died in the crash, Hiru News reported, citing the BBC. A British pilot and a second Greek crew member were injured and taken to hospital.

Firefighters were separately battling a blaze around Porto Germeno on the Gulf of Corinth, where flames crossed a mountain and reached a military firing range, setting off unexploded ordnance. Nearly 500 firefighters were deployed, with reinforcements arriving from France and Romania.

Gale-force winds that had driven the Porto Germeno fire eased, but flames reached the settlement of Veniza, and crews mounted a major effort to stop the fire advancing on the coastal town of Megara. More than 10,000 hectares are believed to have burned, the Greek daily Protothema reported.

In the village of Agios Konstantinos, residents fought the fire themselves. β€œThe 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 was pouring water on the flames alongside his son.

On Kefalonia, a 44-year-old man was arrested on Sunday on suspicion of deliberately starting a fire that broke out in the Pastra area in the south of the island, the Greek news agency ANA reported.

Elsewhere in Europe, wildfires in the French departments of Gironde and Var showed only minor flare-ups, and fires that burned tens of thousands of hectares in central Spain were largely under control, though crews were dealing with re-ignitions. Scientists say the conditions behind this summer’s fires β€” prolonged heat and little rain β€” have been made worse by climate change.