TikTok runs a questionable word filtering system in Germany, according to a report by German public broadcasters.

The popular Chinese social network has blocked posts containing German words related to Nazis, LGBTQ culture and tennis player Peng Shuai, according to research by ARD’s NDR, WDR and Tagesschau.

Users were able to post the offending keywords, but – in a practice known as shadowbanning – the posts were not visible to others.

Words such as “porn” and “sex” were blocked, presumably to protect minors. However, words such as “gay”, “queer”, “LGBTQ” and “homosexual” were also blocked. Other words that have been partially blocked include “transsexual” and “government in exile”.

Words such as “Auschwitz” and “National Socialism” (Nazism) were also blocked. The commemoration of the horrors of the Holocaust is deeply rooted in German culture and law.

Why is ‘Peng Shuai’ blocked?

In response to a request from public broadcasters, the social media platform said: “We have mechanisms in place to automatically filter out potentially harmful comments.”

“We are aware that this procedure was not targeted in this case,” TikTok representatives said, “and we are working at full speed to revise our procedure.”

Another term that drew accusations of potential censorship was the blocking of the keyword “Peng Shuai”. The Chinese tennis player accused a senior Chinese Communist Party (CCP) official of sexual assault and later disappeared from the public eye, sparking an international outcry. She has since made public statements quashing her charges, but rights activists have accused the CCP of intimidating her.

In the case of Peng Shuai, the company claimed that her name was automatically blocked because it contained the letters “Hua”, a pejorative term sometimes used for sex workers in Austria.

The CCP’s grip on Chinese companies

TikTok later removed some of the terms discovered in broadcasters’ searches.

The CCP maintains firm control over many Chinese companies, forcing censorship and other actions beneficial to the party philosophy.

Previous reports found several instances in which TikTok censored terms considered subversive or controversial in China, including content related to ongoing human rights abuses in Xinjiang province.

Last month, the German daily Frankfurter Allgemeine Zeitung discovered that TikTok censored the captions of videos containing the terms such as “re-education camp”, “internment camp” and “labor camp”.

LGBTQ terms have also featured prominently in previous TikTok censorship cases.