At least 60 people have died and dozens are missing as swollen rivers caused by record rainfall swept through towns and villages, leaving cars up-ended, houses destroyed and people stranded on rooftops.
The heavy rains lashed western Europe, with 28 people dead and dozens unaccounted for around the wine-growing region of Ahrweiler, in Rhineland-Palatinate state in Germany.
Half a dozen houses had been brought down after the Ahr river that flows into the Rhine broke its banks, police said.
Authorities in North Rhine-Westphalia state said at least 30 people had also died.
In Belgium, two men died due to the torrential rain and a 15-year-old girl was missing after being swept away by an overflowing river.
Hundreds of soldiers and 2500 relief workers were helping police with rescue efforts in Germany.
Tanks were deployed to clear roads of landslides and fallen trees and helicopters winched those stranded on rooftops to safety.
About 200,000 households lost power due to the floods.
Germany's worst mass loss of life in years
In Ahrweiler, two wrecked cars were propped steeply against either side of the town's stone gate and locals used snow shovels and brooms to sweep mud from their homes and shops after the floodwaters receded.
"I was totally surprised. I had thought that water would come in here one day, but nothing like this," resident Michael Ahrend told Reuters.
"This isn't a war – it's simply nature hitting out. Finally, we should start paying attention to it."
The floods have caused Germany's worst mass loss of life in years.
Flooding in 2002 killed 21 people in eastern Germany and more than 100 across the wider central European region.
Chancellor Angela Merkel expressed her dismay.
"I am shocked by the catastrophe that so many people in the flood areas have to endure. My sympathy goes out to the families of the dead and missing, she said.
In the US for a farewell visit before she steps down following a federal election in September, Merkel promised financial aid for those affected.
"You can trust that all branches of government, federal, state and local, will join forces to do everything they can to save lives, avert danger and alleviate hardship," she said.
Houses collapse in Belgium
In Belgium, about 10 houses collapsed in Pepinster after the river Vesdre flooded the eastern town and residents were relocated from more than 1000 homes.
A rescue operation by firefighters also went wrong when a small boat capsized and three elderly people disappeared.
“Unfortunately, they were quickly engulfed,” said Mayor Philippe Godin.
“I fear they are dead.”
The rain also caused severe disruption to public transport, with high-speed train services to Germany cancelled.
Traffic on the river Meuse is also suspended as the major Belgian waterway threatened to breach its banks.
Downstream in the Netherlands, flooding rivers damaged many houses in the southern province of Limburg, where several care homes were evacuated.
In addition to the fatalities in the Euskirchen region, another nine people, including two firefighters, died elsewhere in North Rhine-Westphalia.
'It was like madness': Floods labelled 'scary, unimaginable'
In the town of Schuld, back in Germany, houses were reduced to piles of debris and broken beams.
Karl-Heinz Grimm, who had come to help his parents in Schuld, said he had never seen the small Ahr River surge in such a deadly torrent.
“This night, it was like madness,” he said.
Roads were blocked by wreckage and fallen trees.
"It was catastrophic," Edgar Gillessen, whose family home had been damaged, said.
"All these people living here, I know them all. I feel so sorry for them, they've lost everything. A friend had a workshop over there, nothing standing, the bakery, the butcher, it's all gone. It's scary. Unimaginable."
Weather experts said that rain in the region over the past 24 hours had been unprecedented as a near-stationary low-pressure weather system also caused sustained local downpours to the west in France, Belgium and the Netherlands.
The equivalent of two months of rain has fallen over two days in northeastern France, according to the French national weather service, with flood warnings issued for 10 regions.
No injuries or deaths have been reported, but forecasters warned of mudslides and more rain Friday.
with AP and Reuters
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