ATHENS, Aug.10 (Xinhua) -- A wildfire which broke out on Elafonisos island in southern Greece on Saturday has prompted the evacuation of a hotel and camping as a precautionary measure, with no injuries reported, according to Greek national news agency AMNA.

The blaze is burning mainly low vegetation, as firefighters' efforts to contain it are hampered by strong winds.

The image is similar in Marathon municipality, some 42 kilometers northeast of Athens. According to preliminary information from the Fire Brigade, the flames are scorching a forested zone not very far away from the starting line of the Athens Classic Marathon race.

Due to the combination of strong winds and a new heat wave which has gripped Greece this week sending temperatures up to 40 degrees Celsius, Greek authorities have declared a state of "red alert" for this weekend.

The General Secretariat for Civil Protection has warned of extreme fire risk (category 5) across many parts of the country.

It is the first time since 2012 that such a high alert is called in Greece, Nikos Hardalias, general secretary for Civil Protection, noted.

For first time the General Secretariat for Civil Protection also sent an sms to Greeks and foreigners residing or vacationing in Greece, in both Greek and English, warning them of the risk and suggesting to "avoid actions which may cause a fire."

The European emergency number 112 is set in operation after years of delay by Greek authorities, following strong criticism regarding the functioning of the state mechanism in last summer's wildfire in a seaside resort near Athens which resulted in 102 casualties.

Greece suffers from destructive wildfires each summer. Most are linked to arson and heat waves.

According to the forecasts of Greek meteorologists, high temperatures will continue until mid-week.