Around 1,500 firefighters were battling multiple forest fires and several bush fires in central and northern Portugal Sunday following a punishing heatwave, prompting the government to implement a "state of contingency".

The fires have been burning in several areas since Thursday, destroying at least two homes, as nearly 250 fires were reported to have started on Friday and Saturday. 

The blazes follow an intense heatwave in Portugal, with temperatures reaching over 40 degrees Celsius this week, and expected to rise in the coming days. 

Scientists say climate change is linked to more extreme and more frequent weather events, including heatwaves and forest fires. 

The Portuguese government issued a national "state of contingency" as the latest fires raged Sunday, which puts rescue personnel on alert. It is above state of alert, but beneath state of calamity and state of emergency. 

The Civil Protection agency said there were some 1,500 firefighters battling blazes in Ourem, Pombal and Carrazeda de Ansiaes municipalities.

In the hamlet of Travessa de Almogadel in central Portugal, pensioner Donzilia Marques was relived to find her house was not damaged as she returned Sunday after being evacuated the night before. 

"The fire arrived 50 metres from the last house in the village... up there everything burned," the 76-year-old told AFP, pointing to the hills between home and the town of Freixianda. 

More than 700 soldiers were dispatched to the area Sunday after the fires destroyed some 1,500 hectares of vegetation, the Civil Protection agency estimated. 

The fires have injured a dozen firefighters and about 20 civilians, but most were treated on the spot for breathing problems or exhaustion.

Prime Minister Antonio Costa cancelled a planned trip to Mozambique to follow the fires at home. 

The government has asked the European Union to activate its common civil protection mechanism, which will allow Portugal to access two water bomber planes stationed in Spain.

"We are facing an almost unprecedented situation in meteorological terms", national commander of civil protection, Andre Fernandes said Saturday. 

Portugal has already seen extreme weather this year, with an extreme drought affecting around 28% of the country's territory in June, compared to just 1% in May.