Germany announced on Tuesday that it was banning a far-right group that refuses to recognize the German state and that has set up aspects of a parallel one of its own that includes a separate currency, ID cards, license plates and even a bank.

On Tuesday morning, 800 police officers were mobilized in seven states and arrested four of the leaders of the group, which calls itself the Kingdom of Germany. Officers also searched buildings where the group was operating.

Peter Fitzek, 59, a former cook who leads the group, and is known to his followers as Peter I, the self-appointed king, was among those arrested. The police said that Mr. Fitzek was being investigated for leading a criminal organization and illegally selling insurance and investments.

The Kingdom of Germany, which the authorities estimate has 1,000 active members, is the largest organized grouping of the so-called Reichsbürger movement.

Adherents of the movement generally claim that the German government is being run by “deep-state operatives” and often use antisemitic and anti-democratic conspiracy theories to justify their resistance to the modern German state.

“The aim of this association is to establish a so-called parallel state and to secede from the Federal Republic of Germany,” Alexander Dobrindt, Germany’s new interior minister, said in Berlin after the raids.