Greece's fire department says the death toll from wildfires that decimated seaside communities near Athens has increased to 79.
Spokeswoman Stavroula Malliri said rescue crews continue to search the areas northeast of Athens that were the worst affected by the fire. Crews have been going house-to-house and searching burned cars and the scorched coastline to locate any further victims.
Malliri said authorities have received dozens of calls for missing people, adding that some of those reported as missing could be among the dead, or might have already returned to their families without authorities having been informed.
There was no official number released as to how many people might be missing. Some people have taken to social media and Greek television stations with appeals for information on their loved ones.
Emergency crews found one group of 26 victims, including families with children clasped in a last embrace as they tried to flee the flames. They were huddled together in a field just 30 metres from the sea near Mati in the region of Rafina, eastern Greece.
Nikos Economopoulos, head of Greece's Red Cross, told Skai TV: "They had tried to find an escape route but unfortunately these people and their kids didn't make it in time. Instinctively, seeing the end nearing, they embraced."
Interior Minister Panos Skourletis described the wildfires as a "Biblical disaster", according to The Times, and said rescue workers were "still searching to see if there are more missing", while mayor of Rafina Evangelos Bournous told the channel: "The number of dead is rising."
Ferocious fires came all the way into the towns, meaning the only safe direction for people to flee was towards the sea where hundreds of people had to be rescued in local fishing boats.
Government spokesman Dimitris Tzanakopoulos said early on Tuesday that Greece had requested US drones "to observe and detect any suspicious activity" after "15 fires had started simultaneously on three different fronts in Athens".
The fire was by far Greece's worst since flames devastated the southern Peloponnese peninsula in August 2007, killing dozens. It broke out in Mati late Monday afternoon and was still burning in some areas on Tuesday morning.
Cecily, 44, from Paris, on holiday with her 15-year-old daughter told The Telegraph: "We were staying in a holiday villa in Mati. We saw the fires outside the house and jumped in our hire car and drove towards the beach.
"There were about 500 people crammed onto the beach. There were no warnings and no help from authorities. The local Greek people came to rescue us in their fishing boats.
"We got in one then were picked up by a military boat which took us to Rafina. All the hotels were full so we slept in the hallway. We booked a flight back to Paris today. We have had no help from anywhere."
Another French tourist Paulina Corvisier, 25, from Lyon, on holiday with her husband and mother-in-law, said: "We ran to the beach. We were all crowded onto the sand and rocks. Then the trees surrounding the beach burst into flames.
"I jumped in the water because I didn't know what else to do. Ash was falling on me from the sky while I was in the water."
Coastguard vessels were combing beaches to find any remaining survivors, with military hospitals on full alert, a government spokesman said.
Mati is in the eastern Rafina region, a popular spot for Greek holiday-makers, particularly pensioners and children at camps, 29 km east of the capital.
Haris Malimagolou from the Red Cross, talking of the harrowing discovery of the 26 victims found together, said: "Some members of our team found 26 bodies in a field next to the sea, we are assuming they were trapped by the fire because it was so strong and so fast. Some were huddled together as if trying to protect each other.
"They were badly burned and have not been identified yet. Their bodies have been transferred to Athens."
He explained that the fire was so devastating because a separate fire at Corinth - some 110km from Mati - started earlier at 11am, so all the fire service resources were sent there.
This region is also very densely populated with a lot of summer houses, old people and children. Malimagolou told the Telegraph the Red Cross have treated about 100 people for both minor and serious injuries
One of the youngest fatalities at this stage is thought to be a 6-month-old baby who died of smoke inhalation, officials said. Of the 156 people injured, 11 were in intensive care, they added.
The coastguard said four bodies were retrieved from the sea. In total, coastguard and other vessels rescued 696 people who had fled to beaches. Boats plucked another 19 people alive from the water.
Greece's fire brigade said the intensity and spread of the wildfire at Mati had slowed on Tuesday as winds died down, but it was still not fully under control.
Greek Prime Minister Alexis Tsipras on Tuesday afternoon declared a three-day period of national mourning, and said after cutting short a visit to Bosnia: "We are dealing with something completely asymmetric. It's a difficult night for Greece."
Greece issued an urgent appeal for help to tackle the fires, saying it needed air and land assets from its European Union partners. Cyprus offered to send fire engines and personnel.
The first major fire broke out in a pine forest near the seaside settlement of Kineta, 30 miles west of Athens between the capital and Corinth.
At least 220 firefighters were on the scene there while five water-dropping planes and seven helicopters helped to fight the blaze from the air. Reinforcements were sent in from across Greece.