"We were driving through the flames all of a sudden in the blink of any eye, to be honest", he said. Several bodies were found in the sea, apparently those of victims who had tried to escape the smoke and flames.
As the search for missing persons continues, a website has been set up to help relatives trace their loved ones.
Greek authorities have rushed to evacuate residents and tourists stranded on beaches in coastal areas early Tuesday as strong winds have fanned the flames of wildfires tearing through woodland and villages in the Athens region.
The wildfires have affected the area of Attica, but has not affected other popular islands such as Crete, Rhodes and Zante.
One survivor, Nikos Stavrinidis, told ABC News that despite the air-conditioning in his auto, he could still feel the heat from outside as he travelled on a highway.
It is Greece's worst fire disaster since 2007, when dozens of people were killed in the southern Peloponnese peninsula.
Alexis Tsipras, the country's prime minister and leader of the Syriza party, declared three days of national mourning but added: "We mustn't let mourning overwhelm us, because these hours are hours of battle, unity, courage and above all of solidarity".
Another, who only just managed to escape with his young baby as the flames engulfed the first floor of his home, said: "Suddenly I started hearing explosions".
Authorities said they would be making use of an unmanned drone from the United States on Tuesday to monitor and track any suspicious activity.
"I am calling my cousin but he does not respond", said Spiros Hatziandreou, who visited the spot. "I've never seen anything like this before in my life". After that, police blocked access to everyone except rescuers.
Buildings burn in the town of Mati.
Showers near Athens Monday missed both fires, but heavy rain is in the forecast for Wednesday. Fueled by gale-force winds, they trapped thousands of people on beaches, roads and in homes.
People watch a wildfire in the town of Rafina near Athens on July
Among the dead is a group of 26 travelers - families, including children, who were found in a final embrace at a seaside resort in Mati.
The blaze struck like a flamethrower, he said, causing smoke inhalation and skin burns.
They were pictured carrying suitcases onto coastguard vessels before being transported to nearby Rafina having waited on a beach for hours. "It burned our backs and we dived into the water", said Kostas Laganos, a middle-aged survivor. "I soaked it, grabbed my wife and we ran to the sea", Mr Passios said.
Cavusoglu also told Kotzias that Turkey is ready to help with rescue and aid efforts.
At least four of the fires had not been brought under control, MSB said, and weather conditions were unfavourable.
Charred bodies lay just 15m (50ft) from the sea, photographer Pantelis Saitas told the Athens-Macedonian News Agency.
Sixty-four people were killed and 250 injured in the deadliest wildfires in Portugal's history in June 2017.
How are the authorities responding?
A senior fire chief went on state TV to appeal to people to leave the area after some tried to stay at their properties.
European Union countries Spain, France, Germany, Italy, Portugal, Lithuania, Denmark, Poland and Austria have also responded to calls for help from Sweden, which was battling 21 active fires nationwide.
Fires are a common problem in Greece during the summer.
The fire posed no immediate threat to Greece's famed ancient monuments, but as it raged inland, children's' summer camps and holiday homes were hastily abandoned.
Casualties soared after fires broke out on three different fronts near Athens on Monday, with the majority found in their homes or cars in Mati, where many houses are surrounded by tall pine trees.More news: Demi Lovato Reportedly Rushed to Hospital Following Overdose
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