Forest fires fanned by strong winds and high temperatures have broken out around Athens and other parts of southern Greece, sending residents fleeing as clouds of smoke billowed over their homes.
The wildfires created a new problem for the government of Prime Minister Alexis Tsipras, which is struggling to obtain a fresh bailout from foreign creditors.
The police said 34 separate fires had broken out on four main fronts in a region stretching from the island of Evia, northeast of Athens, to the southern Peloponnese.
One person has died after inhaling fumes and suffering respiratory problems, but there were no other reports of casualties.
Mr Tsipras urged calm as more than 140 firefighters with 80 fire engines and 11 aircraft battled the flames near Athens, which a Reuters photographer said were near homes.
A neighborhood playground was razed and flames surrounded the local church.
Dozens of people, including elderly women covering their faces with headscarves, tried to put out the flames with buckets of water.
"We all need to stay calm," Mr Tsipras told reporters.
He said he had asked the air force and armed forces for help and had also appealed to other European countries for assistance with extra fire-fighting aircraft.
Forest fires are common during the summer months in Greece, but memories remain vivid of the huge damage and heavy loss of life in 2007, during the most serious outbreak of the past few years.
"The situation is difficult," said Michalis Karagiannis, deputy mayor of Vyronas, one of the suburbs near the flames.
Energy Minister Panagiotis Lafazanis, who spoke to Greek TV from the scene with a protective mask across his face, said: "We are all making an effort to stop the worst."
He was heckled by angry residents who accused him of doing "micro politics" and urged him to "take off your jacket and help".
In the region of Laconia in the southern Peloponnese one fire-fighting aircraft was forced to make an emergency landing.
"Things are very bad," Peloponnese Governor Petros Tatoulis told state television.
"The situation is critical. We are working to prevent casualties."
Adamantia Koroni, deputy head of a hoteliers' association on the nearby island of Cythera, said about 40,000 visitors and residents were left without power on the popular tourist destination "probably until Sunday".