"This is not just a national sports club or nationalist sports club. In its essence, it’s the strategy to build a neo-Nazi militia,” said Alexander Ritzmann, a senior adviser for the Counter Extremism Project.

Ritzmann has been studying the Active Club movement for years.

He says that, in their propaganda, Rundo and his followers liken themselves to Italy's fascist militia known as the Blackshirts or to Adolf Hitler's Stormtroopers.