LISBON- More than 800 firefighters battled on Sunday one wildfire sweeping across central Portugal after being able to control two other blazes that prompted authorities to partially evacuate a village and left 20 people injured, one of them in a serious condition, officials said.

Portugal’s criminal police opened an investigation on the wildfires, internal administration minister Eduardo Cabrita told reporters. He said that local authorities found it strange that all the blazes started between 1430 local time (1330 GMT) and 1530 local time (1430 GMT) on Saturday around the same area.

Strong winds are making it harder for firefighters to put out the remaining wildfire although they have been able to control 60% of the flames, which started on Saturday afternoon in Castelo Branco, a district 225 kilometres (139 miles) northeast of the capital Lisbon, and which has spread the Santarem district.

"We are ready for a difficult day," Belo Costa, a Civil Protection official, told reporters. He added that no houses were currently at risk.

Fourteen airplanes along with 251 firefighters vehicles on the ground are also battling the blazes, as well as 20 soldiers and four bulldozers.

Twelve civilians and eight firefighters were injured in Saturday's fires, Cabrita said. Only one is in a serious condition and remains hospitalised with first and second degree burns.

One of the two districts affected, Castelo Branco, is under yellow alert as temperatures are expected to reach 31 degrees Celsius on Sunday, according to the national meteorological agency.

Ricardo Aires, the mayor of Vila de Rei, one of the affected municipalities, told Portugal's public broadcaster RTP that firefighters and resources were lacking.

The Portuguese president, Marcelo Rebelo de Sousa, said in a statement that he is following the situation closely and sent solidarity to those affected.

In June 2017, a devastating wildfire in the central town of Pedrogao Grande killed 64 people and injured more than 250. The fire was the worst disaster in modern Portuguese history.

(Reporting by Catarina Demony; Writing by Catarina Demony, Joan Faus; Editing by Daniel Wallis and Louise Heavens) ((catarina.demony@thomsonreuters.com; 00351213509216;))