The deadliest flash floods in Spain’s modern history have killed at least 211 people and dozens were still unaccounted for, four days after torrential rains swept the eastern region of Valencia, Prime Minister Pedro Sanchez said on Saturday.

In a televised statement, Sanchez said the government was sending 5,000 more army troops to help with the searches and clean-up in addition to 2,500 soldiers already deployed.

“It is the biggest operation by the Armed Forces in Spain in peacetime,” Sanchez said. “The government is going to mobilise all the resources necessary as long as they are needed.”

The tragedy is already Europe’s worst flood-related disaster since 1967 when at least 500 people died in Portugal.

Meanwhile, volunteers flocked to Valencia’s City of Arts and Sciences centre for the first coordinated clean-up organised by regional authorities. The venue has been turned into the nerve centre for the operation.

In Valencia’s Picanya suburb, shop-owner Emilia, 74, told Reuters on Saturday: “We feel abandoned, there are many people who need help. It is not only my house, is all the houses and we are throwing away furniture, we are throwing away everything.

“When is the help going to come to have fridges and washing machines? Because we can’t even wash our clothes and we can’t even have a shower.”

Nurse Maria Jose Gilabert, 52, who also lives in Picanya, said: “We are devastated because there is not much light to be seen here at the moment, not because they are not coming to help, they are coming from all over Spain, but because it will be a long time before this becomes a habitable area again.” The storm triggered a new weather alert in the Balearic Islands, Catalonia and Valencia, where rains are expected to continue during the weekend.

Scientists say extreme weather events are becoming more frequent in Europe, and elsewhere, 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.

The storms concentrated over the Magro and Turia river basins and, in the Poyo riverbed, produced walls of water that overflowed riverbanks, catching people unaware as they went on with their daily lives, with many coming home from work on Tuesday evening.

In the blink of an eye, the muddy water covered roads, railways and entered houses and businesses in villages on the southern outskirts of Valencia city. Drivers had to take shelter on car roofs, while residents tried to take refuge on higher ground. Spain’s national weather service said that in the hard-hit locality of Chiva it rained more in eight hours than it had in the preceding 20 months, calling the deluge “extraordinary.”