Reports that at least 50 people have been killed came this morning as the Red Cross reported finding 26 bodies in the yard of a villa at the centre of the disaster.
The death toll had previously stood at 24, in Greece’s worst fire crisis for more than a decade.
Nikos Economopoulos, head of Greece’s Red Cross, told Skai TV: “I was briefed by a rescuer that he saw the shocking picture of 26 people tightly huddled in a field some 30 metres from the beach.
“They had tried to find an escape route but unfortunately these people and their kids didn’t make it in time.”
More than 100 have been injured as fires broke out on Monday in the wake of an intense heatwave in the country.
Residents and tourists had been seen fleeing to beaches towards the sea in order to escape the unyielding flames.
Boats and helicopters have been used by emergency workers to evacuate those seeking shelter on one beach.
There are hundreds of firefighters working to get the blaze under control, as authorities ask for international assistance.
Where are the wildfires?
Fires broke out on Monday afternoon in Mati Village, 18 miles east of Athens.
A popular tourist destination, Mati is in the Rafina region of Greece and is home to resorts and holiday villas.
“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.”
The main Athens-Corinth motorway, one of two routes to the Peloponnese peninsula, was closed and all train services were cancelled.
The previous worst fire in recent times for Greece was in August 2007 on the southern Peloponnese Peninsula.
This blaze killed 84 people, including firefighters and lasted until early September.
However, the current wildfires have already surpassed 2007’s death toll, and are continuing to blaze.
Greece has issued a plea for help and declared a state of emergency, with Greek Prime Minister Alexis Tsipras saying: “We are dealing with something completely asymmetric.”
The Prime Minister cut short a visit to Bosnia to return to his country amidst the fires and declared that “all emergency forces have been mobilised”.
“We will do whatever is humanly possible to control it,” he said.
Cyprus and Spain have offered assistance to Greece after their plea requested help in both air and land.
Countries including Italy, Germany, Poland and France have also sent help supplying additional planes, vehicles and firefighters.