"At this moment, we have what I would call hot points rather than active fronts in a few small areas where there are still flames," said Patricia Gaspar, vice-commander of ANPC operations, as reported by Lusa Portuguese News Agency.
"A vigilance aircraft will transmit live images to the command center, enabling us to get a better view of where those hot spots are," she added.
The fire broke out on Friday afternoon last week in the village of Perna da Negra, near the town of Monchique, 250 km south of Lisbon. Strong and changeable winds since then have caused the fire to spread in several directions, in a perimeter that has now reached 100 km. Some 23,000 hectares have burned.
On Wednesday afternoon this week, the flames surged towards the town of Silves, prompting further evacuations overnight.
A total of 299 people have now been evacuated from their homes. There have been 36 people injured, 19 of whom are firefighters. One of the injured, an elderly lady, is said to be in serious condition.
Thursday morning brought cooler temperatures and a reduction in wind speeds, although the wind remains volatile.
Gaspar said the situation had calmed considerably, but cautioned that there was still a possibility the fire could reignite.