Almost every window has a woman clearly on show.

I'm in Brussels at the heart of the EU,

but on a street many who visit this city will never see.

One woman tapping on the window to get the attention of some guys in the street.

Many of them are wearing bikinis and not much else.

Another woman has just drawn back a whole curtain to reveal very skimp simply clad body.

Quite a few men on the street looking at the windows, seeing what the women are like.

We've been told by the local police that this is 85% Nigerian prostitutes.

Okay, we are going to make a left left coming in from the top and then he's going to be the

client hopefully.

I'm in the company of two veteran officers from the West Africa unit of the Brussels police.

Jimmy and Franz have seen it all and dedicated their working lives to breaking the bombs of modern day slavery.

So Franz, one of the policemen is just going to knock on the window and attract the attention of the prostitute.

Yeah, it looks like he... and attract the attention of the prostitute.

Yeah, looks like she thinks he's a real punter, so they're going in.

There's some colleagues here.

Please come in.

Okay.

Hello.

Okay.

Assus.

Come here.

...