In the Rhineland-Palatinate town of Bad Neuenahr-Ahrweiler, a red fire truck pumps out flood water from the garages beneath an apartment building through three giant hoses.

Water is churning at a rate of 18,000 litres per minute, but it will be at least two hours before rescue workers can safely enter the garages. Only then can the grim search for bodies begin.

“If we find a body, we’ll call the Bundeswehr (armed forces), the police and the body disposal service,” said Sven Heich, 44, a volunteer firefighter from the town of Kirn, two hours away.

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On Friday, he found an elderly woman dead in her ground floor flat.

“They are still searching. We will find dead people for sure,” a resident of the town told AFP, while another said he had witnessed a body being carriedaway on   cart by soldiers.

The town of 30,000 people, famed for its thermal baths and wellness tourism, is one of the hardest-hit by severe floods that have killed at least 165 people in Germany.

The pavements are littered with broken furniture, while stunned residents wander the streets in rubber boots and mud-stained clothes.

The number of people missing remains unclear, but authorities have been unable to reach more than a thousand in the western state of Fhineland-Palatinate, mainly because of disrupted communication networks.

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Weeks or months

Some 4,500 rescue workers from the THW federal volunteer agency were helping with the search for those still missing on Monday, as well as 800 police officers across the region.

An airfield just outside the town was serving as a base for helicopters to pick up bodies.

Bad Neuenahr-Ahrweiler has set up a call centre manned by 50 investigators who are responsible for logging who is still missing, police spokesman Ulrich Sopart told AFP.

When someone calls, they give the name of the missing person and explain when they last saw them.

The investigators then record what the person was wearing when they were last seen, as well as any defining physical characteristics, before entering them into a database.

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Because the mobile phone network is down, people are often reported missing three times: by family, friends and colleagues.

This makes it difficult to give exact numbers but “the number of missing people is growing by the hour”, Sopart said.

Once a person is on the list, the investigators will start trying to track them down by visiting their home or contacting relatives.

The search “could take weeks or months”, Sopart said. “But the longer the person is unaccounted for, the greater the probability that they are dead.”

Bodies can also be identified through DNA, but some may never be found.

“We will not tell the relatives until we are 100 percent certain that a person is dead,” Sopart said.

By Jean-Philippe LACOUR