At least 50 people have been killed and more than 100 injured by wildfires in Greece.

The deadliest blazes to hit the country in more than a decade have seen wildfires fanned by high winds rage through holiday resorts near Athens.

Of at least 104 people injured by the fires 69 needed hospital treatment and 11 were in a serious condition, officials said.

It is feared the death toll could increase after rescue crews reported finding the bodies of more than 20 people huddled closely together near a beach north-east of Athens.

The head of Greece’s Red Cross, Nikos Oikonomopoulos, told local television a member of a Red Cross rescue team had told him the crew had found 26 bodies, apparently families.

Burnt out car in Greece Burned cars are seen outside a damaged house in Rafina, east of Athens (Thanassis Stavrakis/AP)

Ministers said more than 700 people had been evacuated by sea by the coast guard.

Greece has sought international help through the EU as the fires on either side of Athens left lines of cars torched, charred farms and forests, and sent hundreds of people racing to beaches to be evacuated by navy vessels, yachts and fishing boats.

Winds reached 50mph as authorities deployed the country’s entire fleet of water-dropping planes and helicopters to give holidaymakers time to escape.

Military drones remained in the air in the high winds to help officials direct more than 600 firefighters below.

“We were unlucky. The wind changed and it came at us with such force that it razed the coastal area in minutes,” said Evangelos Bournous, mayor of the port town of Rafina, a sleepy mainland port that serves Greek holiday islands.

The dock area became a makeshift hospital as paramedics checked survivors when they came off coast guard vessels and private boats.

The operation continued through the night.

Greece Forest Fire People stand in the sea near to cars parked on the beach to protect them from the fire in the town of Mati (AP/Thanassis Stavrakis)

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.

Fleeing drivers clogged highways into Athens, hampering the firefighting effort.

It has been the deadliest fire season to hit Greece in more than a decade.

More than 60 people were killed in 2007 when huge fires swept across the southern Peloponnese region.

“It’s a difficult night for Greece,” Prime Minister Alexis Tsipras said after flying back to Athens from a trip to Bosnia that was cut short.

Authorities said Cyprus and Spain offered assistance after the request for EU help was made.

Greek Fire Service officials issued public pleas for residents in fire-affected areas to comply with evacuation orders and not stay on in an effort trying to save their homes.

Rafina’s mayor said he believed about 100 houses in that area had burned. The fire service was not able to confirm the figure.

Showers that passed over the Greek capital Monday missed the two big fires — one at Rafina, 18 miles to the east, and the other at Kineta, 35 miles to the west.

Heavy rain is forecast across southern Greece on Wednesday.