Police say that the 41-year-old tourist had "an extremely high blood alcohol level", according to the Associated Press.
The American national reportedly suffered only minor injuries after he was beaten by an incensed local. The tourist's assailant escaped the scene of the attack and is being sought by law enforcement on charges of bodily harm.
Police said the USA national is under investigation for violating German laws prohibiting Nazi symbols and that they are still seeking the passerby for causing personal injury, according to the Associated Press.
The tourist also had the insignia of "unconstitutional organizations, which includes Nazi symbols". The name of the tourist was withheld for privacy reasons.
The Nazi salute, Hitlergruß in German, is performed with the right arm straight and pointed forward slightly at an angle upward with palm down. If convicted, the men face a fine or prison sentence of up to three years.
It is illegal to display symbols of Nazism in Germany.