In Greece, thousands of people have fled their homes on the outskirts of Athens as firefighters from across Europe joined crews battling blazes that are threatening the Greek capital. One fire nearly reached the Ancient Olympia archaeological site, where the Olympic Games were held for over a millennium. Greek Prime Minister Kyriakos Mitsotakis blamed the fires on climate change.

Prime Minister Kyriakos Mitsotakis: “Unfortunately, the worst is yet to come, and the night ahead seems menacing. … We are talking about unprecedented conditions following many days of heat waves, which have transformed the whole country into a powder keg.”

Scores of other fires are raging in Turkey, Italy, the Balkans, Albania, Romania, Ukraine and Russia. On Monday, the United Nations Intergovernmental Panel on Climate Change is set to release its first assessment in eight years. The report from the Nobel Peace Prize-winning agency is expected to contain dire warnings over soaring temperatures, rising seas and extreme weather.