Reuters reported that after the collision of two firefighting helicopters while containing a large wildfire near Athens, two people—one Greek citizen and one Danish citizen—were killed, and two other crew members, Greek and British, survived. Greek authorities have launched an investigation into the cause of the accident.

Wildfires sparked by an unprecedented heatwave have so far destroyed more than 100 homes and forced hundreds of people to evacuate. Authorities believe the fire may have been started by sparks from power transmission lines and have arrested two people on suspicion of negligence.

At the same time, an evacuation warning was issued for areas in western Athens, and emergency forces are working to contain the fire. Reuters also reported that wildfires in France and Spain have largely been brought under control, but drought and extreme heat continue to affect different parts of Europe.

In Hungary as well, the Danube’s unprecedented drop in water level for the first time in more than four decades has shut down the country’s only nuclear power plant, and has also sharply reduced Serbia’s hydropower generation. Read the full text here