Around 150 firefighters battled to put out the blaze in the early hours of Friday morning, emergency services in the Andalusia region have said.
Minister of the presidency, health, and emergencies Antonio Sanz Cabello described it as “the most devastating fire to date in our region”, and said the situation was an “unprecedented tragedy”.
The number of dead, which had initially been reported as 12, was revised to 11 by Mr Cabello on Friday morning.
The blaze had spread extremely quickly in a wooded area around the town of Los Gallardos, a municipality of the Almeria province in Andalusia. It particularly affected the nearby hamlet of Bedar.
Mr Cabello said authorities had told residents to stay in their homes and that the deaths appeared to have occurred when people decided to try to evacuate in their vehicles.
Four people died in one car, he said, and they appeared to be British as the steering wheel was on the right-hand side.
He said seven others were found dead after apparently abandoning their cars and attempting to escape on foot along a route that was not part of the evacuation plan.
Juanma Moreno, the leader of Spain‘s southern Andalusia region, wrote in a post on X: “Our deepest condolences to the families of the six people who lost their lives in the Los Gallardos, and the affection from all of us to the municipalities affected by the fire.”
It comes after a wildfire in southern France earlier this week forced the evacuation of more than 10,000 people from two dozen small towns and villages near the Spanish border.
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Europe is warming at more than twice the global average, the World Meteorological Organisation has said, making prolonged heat episodes increasingly likely.
