The battle against major wildfires in Greece continued for a fourth consecutive day as authorities launched an investigation into the fatal collision of two firefighting helicopters that claimed the lives of both pilots.

The crash occurred during an aerial firefighting mission west of Athens. According to Greek authorities, one helicopter's rotor struck the other aircraft, causing it to explode and crash. The victims were identified as a Danish pilot and a Greek pilot. The crew aboard the second helicopter survived after its pilot managed to carry out an emergency landing.

The deaths raise Greece's wildfire-related death toll to five after three firefighters lost their lives last week while battling separate blazes in Crete and the Peloponnese. European Commission President Ursula von der Leyen extended condolences to Greece following the tragedy.

The largest active fire remains west of Athens, where flames continue to threaten populated areas. Residents and tourists from three villages were ordered to evacuate again as the fire advanced toward homes. Near the town of Mandra, aerial firefighting operations resumed, providing critical support to more than 500 firefighters, volunteers, and local residents working on the ground.