The blaze erupted on Tuesday evening, and by Thursday morning it had surrounded the town. “It is continuing unabated,” he said.
A large fire destroyed 80-90% of the Mação municipality at the end of July, Estrela pointed out.
Rescuers had evacuated about 130 people from nearby villages, said Patrícia Gaspar, spokeswoman for the civil protection agency (ANPC).
Emergency teams were particularly worried about the advancing fires around Mação, she said. They hoped that firefighting aircraft, which could not be used at night, would tip the balance in their favour.
Firefighters were also concerned about forecasts for hotter weather, which would increarse the risk of extinguished fires reigniting and blazes erupting at new sites, Gaspar said.
Firefighters and local residents were also struggling to control fires in nearby villages, including Vale de Abelha.
The blazes this year are the deadliest the country has faced. The latest wave has injured 86 people, seven seriously.
In mid-June, wildfires near Pedrógão Grande in central Portugal killed 64 people and injured more than 250 others. In once incident, flames spread so quickly that some people died after being trapped in their cars as they tried to drive to safety.
Fires have destroyed 141,000 hectares of land in Portugal this year, civil protection officials said on Wednesday, citing provisional figures.
Firefighters have tackled more than 10,000 separate fires this year – 2,500 more than at the same period in 2016. The exceptional heat and strong winds had intensified the scale of the destruction, said Rui Esteves, commander of the ANPC.
Police say they have arrested 61 suspected arsonists in connection with the wildfires.
After the deadly infernos in June, Portugal requested international help to battle forest fires for the second time this summer. At the weekend, Spain sent 120 firefighters, 27 engines and three planes to bolster Portuguese efforts, as part of an EU programme of mutual aid in emergencies. Morocco has also sent a firefighting plane.
The fires in June prompted a national debate about forest management and an overhaul of the emergency response plan in those regions.
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