At least 24 people died and more than 100 were injured when a wildfire swept through a small resort in eastern Greece, with many victims trapped by flames as they fled.
The fire in Mati, about 30 kilometres east of Athens, was by far the country's worst since flames devastated the southern Peloponnese peninsula in 200, killing dozens.
The fire, which broke out on Monday, was one of several that raged across the country amid a sweltering heat wave.
"Mati doesn't even exist as a settlement anymore," one woman told Greece's Skai TV. "I saw corpses, burned-out cars. I feel lucky to be alive."
Mati is in the Rafina region which is a popular retreat with local holidaymakers, particularly pensioners and children at holiday camps.
Government spokesman Dimitris Tzanakopoulos said in a televised statement early on Tuesday that the death toll exceeded 20 while more than 88 adults and 16 children were injured.
The Greek coastguard later said the bodies of four more people were retrieved from the sea.
One of the youngest victims was thought to be a six-month-old baby who died of smoke inhalation.
A Reuters witness earlier saw at least four dead on a narrow road clogged with cars heading to a beach for safety.
Hundreds of people had scrambled to the sea as the blaze closed in close to the shore. They were picked up by passing boats.
Some parts of Mati were still smouldering white smoke early on Tuesday. Burned-out cars were scattered outside
gated compounds where three- and four-storey buildings bore signs of fire damage.
"We are dealing with something completely asymmetric," Greek Prime Minister Alexis Tsipras, looking pale, said after cutting short a visit to Bosnia.
Greece issued an urgent appeal for help to tackle fires that raged out of control in several places across the country, destroying homes and disrupting major transport links.
Cyprus and Spain offered assistance after Greece said it needed air and land assets from European Union partners.
Authorities said they would be making use of an unmanned drone from the United States on Tuesday to monitor and track any suspicious activity.
Mr Tsipras and Greek officials have expressed misgivings at the fact that several major fires broke out at the same time,
Wildfires are not uncommon in Greece, and a relatively dry winter helped create current tinder-box conditions. It was not immediately clear what ignited the fires.
Reuters witnesses reported seeing a hillside of homes gutted by flames east of Athens. A mayor said he saw at least 100 homes and 200 vehicles burning.
In a fire earlier Monday, Greek authorities urged residents of a coastal region west of Athens to abandon their homes as a wildfire burned ferociously, closing one of Greece's busiest motorways, halting train links and sending plumes of smoke over the capital.
The main Athens-Corinth motorway, one of two road routes to the Peloponnese peninsula, was closed and train services were cancelled.