It is a spring evening in Germany’s eastern city of Cottbus, and dozens of people have crowded into a small venue to hear a man who once dubbed himself the “friendly face” of National Socialism (Nazism).

Two other men with prior links to extremist groups are also in the room, including a candidate for forthcoming state elections.

They’re all there to hear Matthias Helferich at a youth event organised by members of the prominent far-right party, Alternative für Deutschland (AfD).

The AfD has repeatedly rejected accusations of extremism.

However, by investigating the past of these three men, the BBC has found a clear crossover between AfD figures and far-right networks, some of which are classed as anti-democratic or racist by German authorities.