Wildfires blazed along a smouldering stretch of Portugal's Algarve Thursday, as hundreds of firefighters battled to control flames that have menaced the popular tourist region for a week.
Ferocious fires in southern Portugal, stoked by sweltering temperatures and strong winds, have injured dozens and left a blackened trail of seared forest, charred homes and incinerated cars.
Aircraft scooped water from the sea to drop onto the creeping blaze on Thursday, as firefighters continued their struggle to douse the flames, which have already consumed some 21,000 hectares of forest in the region -- one of Europe's top tourism destinations.
With winds forecast to reach up to 50 kilometres per hour "there is a risk of reactivation in the afternoon along a perimeter that now exceeds 100 kilometres", said national civil protection agency spokeswoman Patricia Gaspar.
The fires have left 36 people injured, one seriously, with 19 of those hurt firefighters,according to Gaspar.
On Thursday more than a thousand firefighters and soldiers were tackling the blazes in the affected zone, which is planted with pines and highly-flammable eucalyptus trees and scored by difficult to reach valleys and ravines.
Fire crews and police conducted an urgent evacuation overnight of homes around the historic town of Silves.
A slight respite on Thursday afternoon enabled local people to leave the schools, gymnasiums and reception centres where they had taken refuge and venture back to their homes.
Dark clouds of smoke and soot from the wildfires had billowed above popular holiday beaches in the region earlier on Thursday, but gusts of wind cleared the skies later in the day.
A Europe-wide heatwave sent the mercury above 45 degrees Celsius in some areas of Portugal at the weekend, intensifying wildfires that began last Friday.
Hundreds of residents and tourists have been evacuated from around Monchique, a popular spa town of 6,000 people some 160 kilometres from Lisbon, where the blazes began.
Prime Minister Antonio Costa on Wednesday warned the blaze would continue to rage "during the coming days".
The difficulty in bringing the fires under control has raised doubt on the effectiveness of measures taken by the Portuguese authorities to avoid a repetition of fires that killed at least 114 people last year.
Firefighters have criticised the lack of coordination, while Costa has drawn flak on social media for remaining on holiday as the flames raged.
The spreading blaze has even necessitated the evacuation of some 29 endangered Iberian lynx to Spain from the national reproductive centre, according to a statement from the country's conservation institute.
In Spain, where more than 700 firefighters continued to battle wildfires in the province of Valencia, authorities said they were hopeful of bringing an end to the threat.
The blaze "has been stabilised", said Valencia emergency services chief Jose Maria Angel, adding the hope of an improving situation over the course of the day.
Authorities have established that the fires were started by lightning during an electric storm on Monday.
A sizzling heatwave across Spain has left 10 people dead in a week.