Authorities in northern Germany filed a criminal complaint against a shopkeeper who hung a "No Jews Allowed" sign in his Flensburg store, calling it an attack on democratic values.

The sign sparked immediate backlash and legal action from Schleswig-Holstein's culture minister Dorit Stenke and the state's antisemitism commissioner, Gerhard Ulrich, who accused the man of incitement to hatred in a joint statement, according to NBC News. (RELATED: Country's Court Orders Suspect In Russian Pipelines' Explosion Extradited To Germany)

In their joint statement, Stenke and Ulrich called the sign "a frightening signal" and "an attack on the principles of our free coexistence," warning that antisemitism is a threat to democracy that "must not be tolerated in any form."

Newsweek identified the shopkeeper as Hans Velten Reisch, who posted a sign reading, "Jews are banned from here. Nothing personal. No antisemitism. Just can't stand you."

Police removed the sign Wednesday after concerns it could escalate tensions and threaten public order, though it remains posted on a wall inside the store, according to Euro News. Reisch told the German newspaper Bild he acted after he "saw what the Jews were doing in the Gaza Strip" and said he had "lost his temper," Newsweek reported.

Flensburg Mayor Fabian Geyer denounced the sign as a reminder of the "darkest chapters of Germany's history" and said it "has absolutely no place in this city," according to Euro News. The incident has also prompted boycott calls from residents.

Despite the message, Reisch said he is "not a Nazi," the outlet reported.