Officials said the fire, which has already destroyed at least 7,000 hectares (17,000 acres) of pine trees since it broke out Sunday afternoon, was still burning but had been stabilised.

Some 500 firefighters from across Portugal and 240 soldiers were still at the scene, in a mountainous region near the town of Silvares, 260 kilometres (160 miles) north of Lisbon, where temperatures soared as high as 40 degrees Celsius (104 degrees Fahrenheit).

In a radio address, the commander of the National Rescue Centre appealed to the population to remain highly vigilant to ensure the fire does not flare up again.

A 65-year-old man burned to death early on Wednesday as he helped firefighters battle the blaze while a man in his 80s was found dead in his car in the same area later that day.

Firefighters said strong winds, high temperatures and the thick brush and steep terrain in the area had made it difficult to put out the fire which officials suspect had been sparked deliberately.

With that fire under control, firefighters were concentrated on another blaze which broke out in the proximity of the nearby town of Vila de Rei on Wednesday afternoon.

A total of 140 firefighters were battling the fire which forced the evacuation of some 70 elderly people from a nursing home on the outskirts of the town.

Local officials decided to evacuate the residents, many of them bedridden, on Thursday after flames came within 400 metres (yards) of the institution.

Prime Minister Jose Manuel Durao Barroso meanwhile vowed to hunt down those responsible for sparking the fires, adding that several people had already been arrested.

"The mayors, those who know the local situation better than anyone, are convinced that there are criminals at work" behind these fires, he said during a visit to Oleiros in central Portugal, which has been devastated by fire.

A dozen people suspected of starting forest fires have been arrested in Portugal since the start of the year, according to the Lusa news agency.

The prime minister, who was accompanied by Interior Minister Antonio Figueiredo Lopes and Agriculture Minister Armando Sevinate Pinto, voiced his support for the families of those who died in the flames on Wednesday.

But critics and the press lashed out at the government, accusing it of doing too little to prevent wildfires from erupting.

"Forest fires cannot be fought, they have to be prevented," the vice-president of Portugal's forest product producer's federation, Emilio Vidigal, told TSF radio.

"Once a fire gets started it is very difficult to contain it," he added.

Vidigal said it could take up to eight months for a landowner to get government approval to clear brush, which can easily ignite during the dry summer months, from a forest.

The Jornal de Noticias daily newspaper meanwhile said government cutbacks had led to forest patrols being carried out only during the day instead of round-the-clock as in the past.

The widespread use of volunteer firefighters in Portugal has also come under scrutiny. Portugal's firefighter force is made up of 10,000 professionals and 30,000 volunteers, many of whom are only trained to fight urban fires.

Some 25,000 forest or brush fires erupted last year in Portugal, burning almost 120,000 hectares (296,000 acres) of land, according to forest service figures.

The amount of land burned each year has increased steadily over the past two decades.

TERRA.WIRE