The flames have advanced westward and have entered Donana National Park, one of Spain's most important nature reserves and home to the highly endangered Iberian lynx.
"The fire has entered in the limits of the reserve, and that is where we are focusing our efforts," Jose Gregorio Fiscal Lopez from the regional Andalusian authority in charge of the environment, told Spanish national television.
Susana Diaz, the regional president of Andalusia, said "there is no risk to the population" after a 1,000 people were evacuated from campsites and houses near the town of Moguer on Spain's southern coast where the fire started on Saturday night.
Diaz said the fire was proving difficult to fight due to the hot weather and shifting winds.