Firefighters are battling a fire on the island of Crete that scorched forests and olive groves and forced more than 1000 people to evacuate, while a fresh conflagration near Athens threatened homes, highlighting Greece's vulnerability to wildfire risks.
Gale-force winds and aridity on Thursday made for tinderbox conditions, hampering Greek authorities' efforts' to tame the fires, as much of Europe baked in an early summer heatwave linked to the death of at least eight people across the region.
A new fire broke out in the Athens suburb of Pikermi on Thursday afternoon, threatening many homes and prompting the evacuation of three settlements as more than 100 firefighters battled to extinguish it.
Thick grey smoke billowed over the area, close to the Athens international airport and Rafina, home to the capital's second largest port. The main avenue linking the suburb to Athens was closed to traffic.
Authorities said there was a high risk of fires also on Friday.
In Crete, around 230 firefighters, along with 46 engines and 10 helicopters, were deployed to contain the conflagration on Crete, which broke out a day earlier near Ierapetra town on the southeastern coast of Greece's largest island.
Authorities declared a state of emergency in the wider municipal area of Ierapetra on Thursday, state broadcaster ERT said.
The blaze encroached upon houses and hotels that were earlier evacuated, stoked by intense winds that "rekindled and hindered firefighting efforts," fire brigade spokesman Vassilis Vathrakogiannis said.
More than 1000 residents and tourists were evacuated from at least four settlements. Most took shelter at an indoor stadium in Ierapetra, while others transferred to hotels in the north or left Crete by boat, authorities said.
Local media reported damage to some homes, and some people were hospitalised with respiratory issues, an official said.
Southeastern Crete saw a massive exodus of about 5000 holidaymakers, George Tzarakis, head of hoteliers in the area, told Reuters, expressing concern over the impact on future bookings. Tourism is a key income earner for the popular tourist island.
Greece and other countries in the Mediterranean are in an area scientists dub "a wildfire hotspot" - with blazes common during hot and dry summers. These have become more destructive in recent years due to a fast-changing climate.
Scientists say heatwaves have arrived earlier this year, spiking temperatures by up to 10C in some regions as warming seas encouraged the formation of a heat dome over much of Europe, trapping hot air masses.
July is usually the most difficult month of the fire season due to high temperatures and strong winds, the fire brigade's Vathrakogiannis said.
Meanwhile, in Turkey, thousands fled as authorities battled wildfires in Cesme and Odemis districts for a second day on the western coastal province of Izmir.
Winds hindered their efforts as the flames approached a main highway to Cesme, local TV footage showed, and thick smoke billowed over mountainous areas.
Italy's health ministry issued red alerts for 18 cities as temperatures poised to soar as high as 38C in major cities.
Temporary blackouts were possible with power consumption surging from the use of air conditioners, Italian Energy Minister Gilberto Pichetto Fratin warned.
Swiss utility Axpo has shut its two reactor units at the Beznau nuclear power plant due to high river water temperatures.