Some cut-off areas went without water, food or power for days.
Rescuers raised the death toll in Spain's worst floods for a generation to 205 on Friday and fears grew for the dozens missing as hopes of finding survivors faded.
The floods that have tossed vehicles, collapsed bridges and covered towns with mud since Tuesday are the European country's deadliest such disaster in decades.
The organisation coordinating emergency services in the hardest-hit eastern Valencia region said 202 people had been confirmed dead there.
Officials in neighbouring Castilla-La Mancha and Andalusia in the south had already announced a combined three deaths in their regions.
Rescuers equipped with helicopters, drones and sniffer dogs waded through water and rummaged through debris in search of dozens of people the authorities believe are still missing.
The government has deployed another 500 troops to the stricken areas to bolster the 1,200 already on site for search, rescue and logistics tasks. Another 500 will be dispatched on Saturday.
The Civil Guard alone had rescued more than 4,500 people as of Friday afternoon, Interior Minister Fernando Grande-Marlaska said.
But three days on from the disaster, hopes of finding more survivors are dwindling.
The courthouse in Valencia city has been converted into a morgue, where health workers wearing smocks carried stretchers covered with white sheets.
'People are desperate'
Some cut-off areas went without water, food or power for days after the floods began, and many roads and railways remain inaccessible.
Engineers worked to remove abandoned cars strewn over warped railway tracks and slabs of tarmac from destroyed roads littered inundated fields, AFP journalists saw.
French volunteers also announced their staff had arrived in Spain on Friday bringing equipment to help clear debris, pump water and rescue victims.
In the devastated town of Paiporta near Valencia city, some residents complained aid was coming too slowly and frustrating the efforts of volunteers.
"There aren't enough firefighters, the shovels haven't arrived," Paco Clemente, a 33-year-old pharmacist, told AFP as he helped clear mud from a friend's house.
Thousands of people remain cut off from the electricity and telephone networks, but it is hoped the estimated number of missing people will fall once connections are restored.
With several places seeing signs of order breaking down, government minister Angel Victor Torres on Thursday vowed an uncompromising response to looting.
Police said they had arrested 50 people for incidents including theft from vehicles and a jewellery store.
In the Valencia region town of Aldaia, Fernando Lozano told AFP he saw thieves grabbing items from an abandoned supermarket as "people are a bit desperate".
"Until things return to normal and the supermarket opens, it's going to be very bad here."
Sports centres and schools were among the sites being used for emergency food distribution, Valencia region leader Carlos Mazon told reporters.
- Wave of solidarity -
An army of thousands of volunteers set off from Valencia on Friday armed with shovels, buckets and shopping trolleys laden with food and nappies to help distressed neighbours in the city's flooded suburbs.
Among them was Federico Martinez, a 55-year-old engineer who headed to help Paiporta residents clear their town of mud.
"We took what we had at home, and now it's time to help. It's emotional, it gives you goosebumps," he told AFP.
Helpers also flocked to Valencia football club's Mestalla stadium where volunteers formed human chains to collect mountains of essential supplies.
Prime Minister Pedro Sanchez hailed "the limitless solidarity and dedication of Spanish society" on X and pledged aid "for as long as it takes".
But the Valencia regional government urged people to stay at home, saying they risked holding up the emergency services rushing to the worst-affected areas.
Pope Francis expressed his solidarity with the victims and their families in Spain, historically a deeply Catholic country.
Sanchez will on Saturday chair another meeting of a special committee made up of top cabinet ministers to follow the crisis.
Marlaska has been sent to Valencia to facilitate the cooperation between the central government and regional authorities in Spain's highly decentralised state.
The storm that sparked the floods formed as cold air moved over the warm waters of the Mediterranean and is common for the time of year.
But scientists warn climate change driven by human activity is increasing the ferocity, length and frequency of such extreme weather events.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
