Hundreds of firefighters, water-bombing planes and helicopters battled forest fires near Athens on Tuesday that saw villages evacuated and part of a major motorway closed, officials said.
With the country reeling under a severe heatwave, a blaze spread at the foot of Mount Parnitha, 30 kilometres (20 miles) north of Athens, sending thick smoke over the city.
The fire service said about 300 people had to be evacuated because of the approaching flames. Police reported helping 70 people to escape from homes threatened by fire.
"Our priority is to save lives hence the decision to evacuate villagers," Civil Protection Minister Michalis Chryssohoidis told reporters in the evening.
Local media reported dozens of children had been rescued from a holiday camp near the Athens suburb of Varympompi, while the motorway linking the capital with the north and south of the country was cut for safety reasons.
The fire brigade said seven water-bombing aircraft, five helicopters, 70 fire trucks and more than 500 firefighters were battling the flames in a zone that includes the former Greek royal family's summer palace of Tatoi and several monasteries.
"There was no wind," one resident told the Open TV channel. "How come the firemen couldn't quickly extinguish the blaze?"
NBA star Giannis Antetokounmpo said he had called off a planned meeting with fans in his home suburb of Sepolia Tuesday evening because of the fires.
"We hope there are no casualties. Obviously we have postponed the party in Sepolia," the Greek-Nigerian tweeted.
Deputy Civil Protection Minister Nikos Hardalias listed 40 active fires on Tuesday.
'Coming hours decisive'
"We are facing extreme conditions with temperatures around 45 degrees Centigrade (113 Fahrenheit)," he said.
"The coming hours will be decisive. The heatwave will last, we are asking people to remain vigilant."
Experts have warned climate change is increasing both the frequency and intensity of the wildfires.
"We are facing the worst heatwave since 1987," Prime Minister Kyriakos Mitsotakis said this week.
In the southern Peloponnese region, 300 kms from the capital, three villages were evacuated after a fire started Tuesday afternoon.
And on the Aegean island of Kos, firefighters were also tackling a blaze.
More than 3,000 hectares (7,400 acres) of pine and olive were burned out by a fire that erupted Saturday near the city of Patras, 200 kilometres (125 miles) west of Athens. It was brought under control on Monday.
A blaze on the Greek island of Rhodes, near the Turkish coast, has been burning since Sunday with firefighters struggling to gain the upper hand.
Turkey is suffering its worst fires in at least a decade, claiming the lives of eight people and forcing hundreds to evacuate in southern areas popular with tourists.