Firefightes work to put out a forest fire near the village of Fato, central Portugal, June 18, 2017. [Photo/Agencies]

PEDROGAO GRANDE, Portugal — A raging forest fire in central Portugal killed at least 62 people as they desperately tried to flee, charring cars and trucks as it swept over roads. The disaster — the worst tragedy Portugal has experienced in decades — shook the nation, with the president declaring that the country's pain "knows no end."Almost 24 hours after the deaths Saturday night, fires were still churning across the forested hillsides of central Portugal. Police and firefighters were searching charred areas of the forest and isolated homes, looking for more bodies.

"It is a time of pain but also ... a time to carry on the fight" against the flames, President Marcelo Rebelo de Sousa told the nation in a televised address Sunday evening after the government declared three days of national mourning.

A huge wall of thick smoke and bright red flames towered over the tops of trees in the forested Pedrogao Grande area, 150 kilometers (95 miles) northeast of Lisbon where a lightning strike was believed to have sparked the blaze Saturday. Investigators found a tree that was hit during a "dry thunderstorm," the head of the national judicial police said.

Dry thunderstorms are frequent when falling water evaporates before reaching the ground because of high temperatures. Portugal is prone to forest fires in the dry summer months and temperatures as high as 40 degrees Celsius (104 Fahrenheit) hit the area in recent days.

At least four other significant wildfires were burning Sunday elsewhere in Portugal but the one in Pedrogao Grande was responsible for all the deaths.

"The dimensions of this fire have caused a human tragedy beyond any in our memory," said Prime Minister Antonio Costa told reporters as he arrived at the scene Sunday. "Something extraordinary has taken place and we have to wait for experts to properly determine its causes."Interior Minister Constanca Urbano de Sousa said the death toll had risen to 62 by the end of Sunday. She said the country's judicial police was expecting to complete the identification of the bodies soon in order to release them as early as possible.

Interior Ministry official Jorge Gomes said firefighting crews were having difficulties battling the fire, which was "very intense" in at least two of its four fronts. He said authorities were worried about strong winds that could help spread the blaze further.

More than 350 soldiers on Sunday joined the 700 firefighters who have been struggling to put out the blaze, schools in the area were closed until further notice and outdoor fires were banned.