You're listening to assignment on the BBC World Service.

I'm Chloe Hajmuthau, investigating the trail of Syrian war criminals

who are hiding in plain sight in European cities.

And a warning, this programme includes graphic descriptions of torture.

So this here, this is what now so-called little Syria.

For example, those bold that they cooked the Syrian vegetable to the models

and the German market began to get that falafel, halloumi, hummus and kibbans.

This is Firas fired. He's showing me around the street in Berlin where many of the cities

Syrian refugees have congregated. We walk past restaurants and shisha cafes,

it's noisy and crowded and it reminds Firas of where he's from.

You can get to have a kind of emotional connection to the home.

But even that feeling, it's been taken from me.

Firas doesn't get to enjoy hanging out here reminiscing about Syria.

He hardly ever comes here. It's a scary, a bit scary like to walk here

for a person who's known as an opposition for the Syrian regime.

This is why I don't come to here, rarely.

Firas is a documentary director and his films tell stories about

the systematic bombing of the civilian population by the Syrian military during the Civil War there.

Back home, he was arrested and tortured. He eventually managed to escape.

But even here in Europe, he doesn't feel safe.

And what he's scared of is other Syrian refugees, supporters of President Bashar Al-Assad,

particularly former militia members who might be acting as the Syrian states'

...