A raging forest fire in central Portugal sent flames sweeping over roads, killing at least 62 people, many of them trapped in their cars as they tried to flee, officials say.

On Sunday Prime Minister Antonio Costa called it “the biggest tragedy” Portugal has experienced in decades and declared three days of national mourning.

A huge wall of thick smoke and bright red flames towered over the top of trees in the forested Pedrogao Grande area some 150 kilometres northeast of Lisbon where a lightning strike was believed to have sparked the blaze Saturday.

At least four other significant wildfires affected different areas of the country on Sunday but the one in Pedrogao Grande was responsible for all the deaths.

Costa said the death toll was lowered from 62 victims because one person had been counted twice, but warned more victims were likely to be found.

More than 350 soldiers joined the 700 firefighters who have been struggling to put out the blaze. Temperatures as high as 40 degrees Celsius in recent days might have also played a part in the inferno.

State broadcaster RTP showed terrifying images of several people on a road trying to escape the intense smoke that reduced visibility to a few metres.

Interior Ministry official Jorge Gomes said firefighting crews were having difficulties battling the “very intense” fire on at least two of its four fronts. There are concerns strong winds could help spread the blaze further.

Schools in the area were closed until further notice and outdoor fires were banned.

He said at least 30 people died inside their cars as they tried to flee between the towns of Figueiro dos Vinhos and Castanheira de Pera.

He said 17 others died right outside their cars or by the road, 11 people died in the forest and two people died in a car accident related to the fire.

Gomes says 54 people were also injured in the fire, five of them seriously, including four firefighters and a minor.

The European Union responded to a call for assistance by Portuguese authorities. Spain sent four firefighting aircrafts on Sunday.

France was also sending three aircraft and Greece’s prime minister also offered to send firefighting help.

French President Emmanuel Macron, Pope Francis and Indian Prime Minister Narendra Modi, expressed solidarity with Portugal.

Spanish Prime Minister Mariano Rajoy tweeted that he is “overwhelmed by the tragedy at Pedrogao Grande.

The Portuguese people can count on our solidarity, support and care.”

– DPA