German lawyers have filed a criminal complaint against Facebook founder and CEO Mark Zuckerberg over anti-Semitic speech on the social networking site. There was no immediate response to the complaint from Zuckerberg.

Germany has strict laws against hate speech given its experience under Adolf Hitler. It is illegal to incite hatred and to circulate or display Nazi symbols in Germany and if Zuckerberg is found guilty on those charges, he could face a fine of up to $163m (€150m).

A spokeswoman for the Hamburg prosecutors told Fortune that they are still examining the merit of the lawyers' complaint before deciding whether or not to proceed against Zuckerberg.

"I think Facebook has changed German society — not for the good," Bavarian lawyer Chan-jo Jun told Vice News. "I wanted to find out if the German legal system would prevail against an American company."

Jun has compiled a list of more than 300 Facebook pages and posts that contain swastikas and other Nazi-related images as well as calls for violence against the Middle Eastern and North African immigrants who have flooded Germany over the past year.

Facebook has removed some of them from the internet, but many others are still up. One post depicts President Obama wearing a yarmulke and Orthodox Jewish-style side curls with the label "Nobel Zionism Prize." An accompanying message asks: "Why is this man is not sitting in a concentration camp?"

Jun and Cologne attorney Christian Solmecke moved against Zuckerberg after German authorities refused to take action against Facebook's German executives in 2015. Prosecutors said the executives were not responsible for the behaviour of the California company.

Jun and Solmecke then filed a complaint targeting a Facebook executive who oversees the site's operations in northern, central and eastern Europe. Prosecutors are now investigating the lawyers' claims in that case.

Zuckerberg has been trying to head off any German crackdown with a charm offensive expressing outrage at the hate speech that litters Facebook. He insisted at a town hall meeting in Berlin in February that Facebook is struggling mightily against hate speech.

"Really, our education and learning more about German culture and German law has led us to change our approach on that to now include hate speech against migrants as an important part of what we have no tolerance for on Facebook," he said.

Zuckerberg added: "There is still work to do, we want to do that. We hear the message loud and clear and we are committed to doing better."

Zuckerberg was previously caught on tape telling Chancellor Angela Merkel that he would "work" on the problem when she grilled him about what Facebook was doing about hate speech.

In early January Facebook launched its "Initiative for Civil Courage Online" in Berlin, pledging $1.1m (€1m) to support non-governmental organisations in their efforts to counter racist and xenophobic posts.