Hundreds of firefighters backed by fire engines and water bombing aircraft battled the blaze that broke out on Sunday near the village of Varnavas 35km north of Athens and torched homes, vehicles and swathes of bone-dry forest.
Stoked by gale-force winds, the blaze leapt from a wooded, hilly area into the suburbs on Monday, choking the city with smoke and ash and stirring panic in neighbourhoods that had not seen such a fire so close to the centre in decades.
Hundreds of firefighters are battling a wildfire raging out of control on fringes of Athens. (AP PHOTO)
It reached Vrilissia, around 14km from central Athens, a day ago, where one person was found dead, according to the fire brigade.
The cause of the wildfire was not yet determined.
Pockets of fire remained around northern Athens, but the fierce blazes seen on Monday had subsided and the thick smoke that covered central Athens had mostly lifted.
"There is no active front, but scattered outbreaks," Climate Crisis and Civil Protection Minister Vassilis Kikilias said in a televised statement.
Winds were expected to pick up again later in the day on Tuesday and the country will remain on high fire alert until Thursday, with strong winds and temperatures forecast to reach up to 40C.
"The overall picture looks improved but there are still many fronts in various areas," said a fire brigade official.
Wildfires have been a common feature of Greek summers for years, but climate change has brought hotter weather and less rain, ideal conditions for large-scale fires.
The southern European country experienced its warmest winter on record this year and was on track for its hottest summer, with scant rain in many areas for months.
The worsening situation was mirrored across southern Europe, including in Spain and the Balkans.
Smoke looms over Acropolis hill as a wildfire continues to burn in the northern part of Athens. (AP PHOTO)
The Greek fire left in its wake abandoned homes, burned cars and charred fields. Local newspaper Proto Thema said the damage spanned 100 square kilometres and included 100 homes.
"My house was utterly destroyed, even the walls fell down. There's nothing left," said Sakis Morfis, 70, a Vrilissia resident.
"There is nothing left. There's no morale, no courage, there's no money anymore, everything was destroyed... The only thing I cared about was saving my dogs, so I left everything (else) behind."
The European Commission on Tuesday announced that it was activating a system for European countries to help Greece battle ongoing wildfires.
At a press conference, a commission spokesman said the support to Greece included: two planes from Italy, two helicopters from France and Serbia and ground firefighting crews from the Czech Republic, France, Italy, Romania and Serbia.
Romanian, Maltese and Moldovan firefighters were already in Greece, the spokesman said.
More than 30 areas were forced to evacuate, along with at least three hospitals, with power cuts in parts of the wider Athens region. Passenger ferries heading to the port of Rafina northeast of the capital were diverted.
Police have helped evacuate more than 250 people, and some residents spent the night in shelters.
with DPA
