The death toll from devastating flash floods in eastern Spain climbed to 158 on Thursday, with rescue teams still searching for those missing in what could become Europe's worst storm-related disaster in over five decades.

"There's a total of 158 people to which must be added dozens and dozens of missing," Angel Victor Torres, minister in charge of cooperation with Spain's regions, told a press conference.

A year's worth of rain fell in eight hours in parts of the Valencia region on Tuesday.

The tragedy is already Spain's worst flood-related disaster in modern history, and meteorologists say human-driven climate change is making such extreme weather events more frequent and destructive.

In 2021, at least 185 people died in heavy flooding in Germany. Prior to that, 209 people died in Romania in 1970 and floods in Portugal in 1967 killed nearly 500 people.

Rescue teams on Thursday discovered the bodies of eight people, including a local policeman, who had been trapped in a garage on the outskirts of the city of Valencia, Mayor Maria Jose Catala told reporters.

In the same neighbourhood of La Torre, she said, a 45-year-old woman was also found dead in her home.

Thousands of people carrying bags or pushing shopping trolleys could be seen on Thursday crossing a pedestrian bridge over the Turia River from La Torre into Valencia city centre to stock up on essential supplies such as toilet paper and water.

Opposition politicians accused the central government in Madrid of acting too slowly to warn residents and send in rescue teams, prompting the Interior Ministry to say regional authorities were responsible for civil protection measures.

"Those people wouldn't have died if they had been warned in time," Laura Villaescusa, a neighbour and manager of a local supermarket, told Reuters.

Maribel Albalat, mayor of the nearby town of Paiporta, said residents were not warned of the imminent danger of flooding. She said 62 people had died in her town.

"We found a lot of elderly people inside their homes and people who went to get their cars. It was a trap," she told TVE.

In Godelleta, a town 37 km (23 miles) west of Valencia city, Antonio Molina, 52, described how he survived by clinging to a pillar on a neighbour's porch on Tuesday as water reached his neck.

Molina's home suffered two major floods in 2018 and 2020 and he blamed authorities for allowing construction of residential buildings in depressions where water accumulates.

"We don't want to live here anymore," he said, tearfully. "As soon as we get a couple of raindrops, we're already checking our phones."

The floods have battered Valencia's infrastructure, sweeping away bridges, roads and rail tracks, and submerged farmland in a region that produces about two-thirds of Spain's citrus crops like oranges, which the country exports globally.

About 80 km (50 miles) of roads in the eastern region were seriously damaged or impassable, said Transport Minister Oscar Puente. Many were blocked by abandoned cars.

"Unfortunately, there are dead bodies in some vehicles," Puente told reporters, adding that it would take two to three weeks to re-establish the high-speed train connection between Valencia and Madrid.

Visiting a rescue coordination centre near Valencia city, Spanish Prime Minister Pedro Sanchez urged people to stay at home due to the threat of more stormy weather.

"Right now, the most important thing is to safeguard as many lives as possible," he told reporters.

In the hard-hit rural town of Utiel, some 85 km (53 miles) inland, the Magro River burst its banks, sending up to three metres (9.8 feet) of water into the mostly single-storey homes.

Utiel's mayor, Ricardo Gabaldon, said at least six people died in the town of about 12,000, most of them elderly or disabled people who were unable to clamber to safety.

Residents used water pumps carried on tractors as they started to clean up on Thursday, with children helping to sweep the sidewalks. Ruined household appliances and furniture were piled up in the middle of roads, and elderly people struggled to walk in the slippery, mud-coated streets.

Pope Francis said he was praying for the people of the region. "I'm close to them in this moment of catastrophe," he said in a video posted on X.

Research group Climate Central said in a report on Thursday that a low-pressure system behind Spain's floods had tapped into an “atmospheric river” carrying excess moisture from the unusually warm Tropical Atlantic.

According to its Climate Shift Index: Ocean, human-caused climate change has made these elevated sea surface temperatures at least 50 to 300 times more likely.