At least 42 people have died and over 50 missing after heavy rains and floods lashed western Germany, police said on Thursday, adding that the rising waters led several houses to collapse. The flash floods caused rivers to burst their banks that led to sweeping away homes and flooded cellars.

Here is what we know so far.

What is the cause of the floods?

Neighbouring country Belgium has been experiencing heavy rains for several days. This has caused the banks of the rivers situated in the French-speaking region of Wallonia to burst. This has raised the level of water in Western Germany as well causing flash floods.

Which are the most affected areas?

The provinces of Liege and Namur were especially affected, with the resort town of Spa completely flooded. Rhineland-Palatinate and North Rhine-Westphalia (NRW) states were the worst hit in Germany by the deluge. Eight people died in the Euskirchen region south of the city of Bonn, reported Reuters.

Casualties so far

In total, at least 42 people have been reported dead

due to heavy floods and incessant rains in Germany. Out of this, over least 18 people died in the region around the western town of Ahrweiler alone, local officials reported. Over 50 people are missing.

How dangerous are these floods?

These floods have caused Germany’s worst mass loss of life in years killing 42 people. The threatening floods of 2002 killed 2021 people in eastern Germany and over 100 across Europe.

German Chancellor Angela Merkel, who is in the US ahead of a meeting with President Joe Biden, said she was “shocked by the disaster”.

NRW leader Armin Laschet, who is running to succeed Merkel in the September elections, cancelled a party meeting in Bavaria to survey the damage in his state, Germany’s most populous.

“We will stand by the towns and people who’ve been affected,” Laschet, clad in rubber boots, told reporters in the town of Hagen.