Raging forest fires in central Portugal have killed at least 57 people, most of whom burnt to death in their cars, and injured scores of others, reports AFP citing government officials.

Nearly 600 firefighters and 160 vehicles were dispatched late Saturday to tackle the deadly fire, which broke out in the afternoon in the municipality of Pedrogao Grande, about 50 kilometers from Coimbra, before spreading fast across several fronts. “Unfortunately, this seems to be the greatest tragedy we have seen in recent years in terms of forest fires,” Prime Minister Antonio Costa said.

He also said at the Civil Protection headquarters near Lisbon, “The number of fatalities could still rise,” “The priority now is to save those people who could still be in danger.”

The European Union said it would provide firefighting planes following a request from Lisbon. “France has offered three planes through the EU Civil Protection Mechanism and they will be quickly sent to assist the local emergency efforts,” EU Commissioner for Humanitarian Aid and Crisis Management Christos Stylianides said.

Portugal was sweltering under a severe heatwave across the weekend, with temperatures exceeding 40 degrees Celsius (104 degrees Fahrenheit) in several regions. Some 60 forest fires broke out across the country during the night, with around 1,700 firefighters battling to put them out.

Secretary of State for the Interior Jorge Gomes said 57 people burned to death, mostly trapped in their cars engulfed by flames in the Leiria region. At least 59 were injured.

“The fire is still raging on four fronts,” he said, of which two were spreading “violently”.

“It is difficult to say if they were fleeing the flames or were taken by surprise,” Gomes said, speaking of the dead.