ATHENS: A raging forest fire threatened homes near Athens on Saturday, causing authorities to declare a state of emergency and order residents to evacuate as they worked to bring the blaze under control.

"This is one of the worst fires ever to strike the eastern Athens area," civil protection authority official Dimitris Karamessinis told Skai television.

A force of 120 firefighters with 35 fire engines, nine water-bombers and five helicopters assisted by army water trucks battled the fire in the communities of Grammatiko, Varnavas and Kalentzi around 40 kilometres (25 miles) northeast of the capital.

Greek media reported that several homes burned down but the fire department could not confirm the reports.

As smoke billowed across the eastern Athens sky, the blaze evoked memories of a 2007 wave of wildfires that killed 77 people and destroyed thousands of hectares of forest, including part of the Mount Parnitha national park northwest of Athens.

Authorities declared a state of emergency and the fire department ordered an evacuation but television footage showed many residents still defending their homes with water hoses.

"We call on people who are near the area to promptly leave for their own safety and to avoid interfering with the firefighters' work," fire department spokesman Yiannis Kapakis told reporters.

The fire comes just two days after another major blaze in the capital's industrial zone.

On Saturday, television footage showed a military truck towing away anti-aircraft missiles. A military barracks is located near the area of the fire.

The blaze broke out on Friday and burned through pine forests in an area with widely dispersed rural and summer homes.

A strong and constantly shifting wind fed the flames, the fire department spokesman said.

"This is a difficult fire because it is in a mixed area with homes and forest, meaning that firefighters are focusing their attention on protecting lives and properties," he said.

Officials said the fire raged out of control during the night when water-bombers were unable to fly.

With temperatures frequently running above 40 degrees Celsius (104 Fahrenheit) and seasonal strong winds, Greece is particularly vulnerable to summer fires that claim thousands of hectares of forest and agricultural land.

Other fires raged on the central Aegean island of Skyros and the Ionian island of Zakynthos, which has been hit by repeated blazes this summer.

On Thursday a brush fire destroyed at least two factories and a number of containers and trucks, according to local officials in the industrial zone of Magoula, west of Athens.

The fire also ravaged around 1,000 hectares of forest and brush, media reports said.

The 2007 wave of wildfires killed 77 people and destroyed over 250,000 hectares of land, mainly in the Peloponnese and the island of Evia.