Temperatures of more than 104 Fahrenheit and strong winds have fanned more than 150 wildfires in different areas of the country in recent days, adding to the conflagrations in Turkey and other areas of the Mediterranean.
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More than a dozen villages have been evacuated on the island of Evia near Athens since Tuesday, with some 85 people rescued by boat from a beach, as the wildfire scorched pine trees and sent clouds of ashes and smoke spiraling into the air. Miles away, skies in Athens were darkened.
Authorities cleared more people on Evia on Thursday as church bells rang, warning that the fire was approaching. More than 170 firefighters with 52 engines and six aircraft were operating in the area.
Two villages were evacuated in the Peloponnese region on Wednesday as a blaze raged near the archaeological site of the ancient Olympics.
After an all-night battle with the flames, firefighters appeared to have saved the site in ancient Olympia, with the ancient treasures out of danger, Culture Minister Lina Mendoni told ANT1 television.
The site, where the Olympic flame begins its journey to the city hosting the modern Olympics, is one of Greece's most popular tourist attractions. It had also been threatened by fire in 2007.
Reinforcements arrived from Cyprus and from France and two aircraft from Sweden were expected later on Thursday as firefighters prepared for another difficult day.
Fires that had threatened houses on the northern outskirts of Athens on Tuesday were under control, with firefighters and aircraft still working in the area.
In Turkey flames that threatened a coal-fired power station in the country's fire-ravaged southwest were extinguished, local authorities said on Thursday, after workers and residents were evacuated overnight by ship when fire broke out in the plant's grounds.
Firefighters continued to battle blazes which President Recep Tayyip Erdogan has described as the worst Turkey has suffered, devastating tens of thousands of hectares of forest and forcing thousands of Turks and tourists to flee.
Eight people have died since the fires first broke out last week and environmentalists had warned of fresh danger as the flames encroached on the power plant.