People in a flooded area after heavy rains and floods in Alora, Spain on October 29 2024. Photo: Reuters/Jon Nazca

Rescuers using dinghies worked in the dark to scour the floodwaters, rescuing several people, television pictures from the town of Utiel showed, and on Wednesday emergency services were working to reach the worst-hit areas.

Carlos Mazon, regional leader of Valencia, said some people remained isolated in inaccessible locations.

“If (emergency services) have not arrived, it's not due to a lack of means or predisposition, but a problem of access,” Mazon told a press conference, adding reaching certain areas was “absolutely impossible”.

Dozens of videos shared on social media overnight appeared to show people trapped by floodwaters, with some climbing into trees to avoid being swept away.

Firefighters could be seen freeing drivers whose cars were stranded in flooded streets in the town of Alzira, online videos showed.

Emergency services in the region urged citizens to avoid all road travel and to follow updates from official sources.

A military unit specialising in rescue operations was deployed in some places to help local emergency workers.

Spain's state weather agency Aemet on Tuesday declared a red alert in Valencia, a major citrus-growing region, with some areas such as Turis and Utiel recording 200mm ) of rainfall. It has since lowered the alert to yellow as rain had largely stopped.

Trains to Madrid and Barcelona were cancelled due to the flooding, and schools and other essential services were suspended in the worst-hit areas.

Lower house speaker Francine Armengol said Wednesday's parliamentary session would be called off because of the disaster.

The death toll appeared to be the worst in Europe from flooding since 2021, when at least 185 people died in Germany.

It is the worst flood-related catastrophe in Spain since 1996, when 87 people died and 180 were injured in a flash flood near Biesca in the Pyrenees.

Scientists said extreme weather events in the region are becoming more frequent due to climate change. Meteorologists think the warming of the Mediterranean, which increases water evaporation, plays a key role in making torrential rains more severe.