Three water-dropping helicopters and more than 200 firefighters were at the scene of the biggest blaze near Torres Novas, some 120 kilometres (75 miles) northeast of Lisbon, firefighters said.

Dozens of people were evacuated from the region because of the approach of the flames which have already engulfed at least four homes, they added.

"Many people are in a state of panic, getting buckets and hoses ready in anticipation of the worst," the mayor of Torres Novas, Antonio Rodrigues, told news radio TSF.

The fire forced police to close the nation's main highway linking Lisbon to second-city Oporto in the north along a 20 kilometre stretch near Torres Novas, for more than three hours, national news agency Lusa reported.

Police meanwhile evacuated hundreds of people from three beaches in southern Portugal because a forest fire was spreading rapidly through mountain brush towards the Atlantic ocean.

The fire, which broke out on the Serra da Arrabida mountain range some 30 kilometres south of Lisbon early Sunday afternoon, had already destroyed a large protected area and threatened numerous homes, the mayor of the nearby city of Setubal said.

"The situation is very worrying at the moment, the fire is creeping towards the beaches," Carlos Sousa told TSF radio.

More than 160 firefighters aided by three water-dropping helicopters were battling the blaze on the Serra da Arrabida, an area rich in Mediterranean plants and birds which is a popular weekend get-away for Lisbon residents.

Another large fire was threatening homes in the southern Monchique mountains in the province of Algarve, one of Europe's top tourist destinations.

At least two homes in the mountain region had burned to the ground and some 40 people have been moved to a temporary shelter, Monchique mayor Carlos Tuta told cable news channel Sic-Noticias.

The Monchique mountains are about 20 kilometres from the Algarve coast where most of the resorts and hotels that are popular with foreign tourists are located.

Portugal is in the grip of a heat wave which has sent temperatures soaring above 40 degrees (104 degrees Fahrenheit) across large parts of the country for the second consecutive day.

Firefighters warned earlier Sunday that the entire country was at risk of wildfires because of the high temperatures.

The government has been under pressure to improve its ability to tackle wildfires after blazes last summer destroyed more than 400,000 hectares (990,000 acres) of scrub and woodland as well as around 100 homes and claimed 20 lives, including those of two firefighters.

The wildfires, which hit the country during a bout of high temperatures that gripped much of Europe in 2003, caused more than one billion eurosbillion dollars) in damage according to government estimates.

TERRA.WIRE