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Here, foreign citizens are offered Swedish postal addresses for a few hundred bucks a month, mattress places for a few thousand bucks and false identities.

SVT Nyheter calls a man in his 40s who in an advertisement states that he sells addresses.

- We must meet, he says when asked how we should proceed.

Can make big money

The man explains that the address is in Botkyrka south of Stockholm and that the price is SEK 500 a month.

We ask how the arrangement works for those who have bought an address.

- If there is mail, I will call you, the man says.

SVT Nyheter has identified several apartments where around 100 people are registered.

Anyone who sells addresses can thus earn tens of thousands of kronor.

It is clear that there are connections between several of the addresses.

During the inspection, we find several people who have been registered at more than one of the identified apartments.

Sellers are described as "terrible"

Foreign citizens from a certain country often register in the same apartment.

At an address in western Stockholm there are many people from Mongolia, in northern Stockholm there is an address where a large number of people from Uzbekistan are registered and in southern Stockholm there are just over 100 citizens from Georgia registered in one and the same apartment.

A person with insight into the black market describes that the people behind the addresses have different good reputations.

A woman south of Stockholm is described as "human" and distributes the mail on time, while a man in northern Stockholm is described as "terrible" and cheats people out of money.

Striked at "goalkeeper address"

The police describe the apartments as "goalkeeper addresses".

This week, they attacked such an apartment south of Stockholm.

"The suspect has, for a fee, let people with coordination numbers have their mail to the apartment," the police write.

The person behind the address is now suspected of tax offenses.