"We have a new fire front today in Ancient Olympia. There are 310 firefighters deployed there", Hardalias said at a briefing.
The site of the Olympics birthplace saw one of the worst wildfires over the past few days. Residents from 32 nearby settlements were evacuated. The fire approached the Archaeological Museum of Olympia and the International Olympic Academy.
The Greek authorities are evacuating people from Lake Marathon in eastern Attica, which is a major source of water for Athens.
The wildfire situation in Attica and Euboea is getting worse due to strong winds.
Greece and other countries in the southeast Mediterranean region are experiencing the worst heatwave since 1987. Temperatures are rising to 44 degrees Celsius (111.2 degrees Fahrenheit), which, in combination with the dry climate and strong winds, have fueled intense wildfires throughout the area in recent weeks.
On Thursday, a total of 60 villages and settlements were evacuated in southern Greece, with 57 out of 99 fires detected on Thursday still burning into the evening.