A major fire south of the Greek capital raged for the second day Sunday, as gale-force winds were rekindling the flames and three new fronts broke out.
Local officials said several homes had been burned, while three firefighters were injured in the blaze Saturday.
More than 250 firefighters and soldiers using more than 60 vehicles were battling the flames in a sparsely populated area south of Athens, along with four water-dropping planes and a helicopter, the fire department said. Another 45 firefighters and 15 vehicles were being sent from other areas.
Greece appealed to the European Union for help. Italy was sending another two water-dropping planes Sunday morning, Citizens' Protection Minister Eleftherios Economou said. Athens was also awaiting a response from France and Croatia.
Four people were to appear in court later Sunday after being arrested for allegedly accidentally causing the blaze while carrying out welding work at a construction site.
By Saturday night, the fire was raging on a 12-kilometer (7.5-mile) front to the west and south of the town of Keratea, 50 kilometers (30 miles) south of Athens.
Fire department chief Panagiotis Bonatsos told state NET TV that three new fronts had broken out within the space of half an hour Sunday morning, and appealed to the public to avoid carrying out any outdoor work that could spark fires.
Power was cut to the area to facilitate water-dropping planes, authorities said. Strong north winds were fanning the flames and hampering efforts to control the blaze, which was burning near sparsely populated areas.
Economou said more than 30 fires had broken out across the country on Saturday, but most were brought under control. The risk of new fires was considered high, after several days of hot temperatures followed by strong winds across most of Greece.
The blazes were being fought as Greeks voted in a national election that could determine whether their indebted nation stays in the euro.
Forest and brush fires are common in the hot, dry summer months in Greece. In the deadliest outbreak in decades, more than 60 people were killed when forest fires raged across southern Greece in 2007.