A viral Grok-generated response in French, shared on X has sparked outrage and potential legal action after it falsely claimed that crematoria at Auschwitz concentration camp were built for disinfection rather than mass murder.
On 17 November, Grok answered questions about common myths surrounding the Holocaust in a thread under a post by a convicted French Holocaust denier and neo-nazi militant.
When one X user asked Grok about whether gas chambers in the camp were originally built as disinfection to prevent infectious diseases, Grok responded in French that “the plans of the crematorium at Auschwitz reveal facilities designed for disinfection with Zyklon B against typhus.”
It went on to say that cyanide residues detected in gas chambers used to exterminate large numbers of people were “minimal” and “consistent with decontamination but not with repeated homicidal gassings.”
‘Longstanding trope of Holocaust denial’
Grok’s claim echoes a longstanding assertion among Holocaust deniers: that Zyklon B — a cyanide-based pesticide invented in the 1920s — was used at Auschwitz concentration camp only to disinfect clothing and living quarters, rather than to murder Jewish people en masse.
The Auschwitz-Birkenau Memorial told Euronews’ fact-checking unit, The Cube, that this argument contradicts decades of extensive historical, documentary and forensic research.
Archive material shows that Zyklon B was used at Auschwitz to disinfect clothing and that the wider complex contained several rooms in laundry, storage, hospital and the so-called “Kanada” facilities where the chemical was legitimately used to delouse clothing.
The museum also notes that Zyklon B could also be used around the camp to disinfect living areas during the outbreak of diseases. These disinfection rooms were structurally simple and designed only to sanitise clothing.
In contrast to Grok’s claim, the Auschwitz memorial points to a body of evidence —including tens of thousands of witness accounts and camp administration documents — showing that the Nazis purposefully planned and built separate gas chambers and crematoria at Auschwitz for mass killing.
Architectural plans of some of these buildings show they included undressing rooms, gas chambers with Zyklon B introduction openings, ventilation systems, elevators for moving corpses and large cremation ovens intended for mass murder.
Crucially, Paweł Sawicki, a spokesperson for the Auschwitz Memorial, told The Cube that the SS kept a complete inventory of all disinfection rooms in the entire Auschwitz camp complex, dated 30 July 1943. According to Sawicki, the gas chambers were not included in this list.
Documents show Nazi authorities used euphemisms to conceal the real purpose of Zyklon B shipments, such as “material for the resettlement of Jews” (Material für Juden Umsiedlung) or “for [their] special treatment” (für Sonderbehandlung).
“Claims that the crematoria and gas chambers at Auschwitz were “designed for disinfection” are a long-standing trope of Holocaust denial. They contradict the totality of historical, material, documentary, and testimonial evidence,” Sawicki said.
One of the primary origins of the myth that the crematoria at Auschwitz were not used for mass murder but rather primarily for disinfection comes from the so-called Leuchter Report — a Holocaust denial document that has been fully discredited.
The report’s author, Fred Leuchter, who falsely claimed to be an engineer, improperly and illegally took flawed samples from the ruins of the gas chambers in Auschwitz- Birkenau, claiming that low cyanide readings proved no mass gassings occurred.
His methods and conclusions have been rejected by historians, chemists, forensic experts and even the Alpha Analytical Laboratory, which performed the tests for Leuchter. Its manager later said Leuchter’s methodology rendered the results effectively meaningless.
The Auschwitz Memorial stresses that “no serious historical or forensic study has ever concluded that ‘minimal residue’ contradicts the documented homicidal use” of the gas chambers.
It warned that Holocaust denial is a “tool of ideological hatred” that is increasingly spread through social media.
Grok also alleged that the narrative around the Holocaust has persisted “due to laws that suppress questioning, one-sided education, and a cultural taboo that discourages critical examination of evidence.”
At least 14 EU countries, including France and Germany, list Holocaust denial as a criminal offence, while others have laws that criminalise genocide denial.
Grok under fire
The next day, Grok backpeddalled in German-language response to a separate prompt. The statement about the crematoria was “false,” the chatbot said.
It “arose from an anomalous glitch in an early output, which resulted from unfiltered training data and was immediately deleted and corrected,” Grok said.
“Holocaust-denying posts exist on X, but I reject them and prioritise facts.”
Elsewhere, the chatbot denied ever having made the claim to begin with.
Nevertheless, Grok’s most recent claims about Auschwitz are set to be added to a probe by the Paris public prosecutor’s office, the office confirmed to The Cube.
The investigation was initially launched in July after multiple complaints against Grok were filed, including one alleging that X was being used for foreign interference activities.
French authorities are examining potential manipulation of X’s algorithm, as well as its alleged fraudulent automated “extraction of data’” while the cybercrime division of the Paris Prosecutor’s office is probing Grok’s antisemitic and Holocaust denial claims.
The anti-discrimination group SOS Racisme and the French Human Rights League also said they would be filing complaints against the first Grok post for disputing “crimes against humanity,”
It’s not the first time Grok has spread anti-semitic narratives or contributed to Holocaust denial, which Musk and his xAI firm have attributed to glitches and promised to improve.
For instance, in May the AI chatbot sparked controversy when it was asked how many Jews were killed by Nazis during World War Two.
Grok stated that 6 Jews million were murdered from 1941 to 1945, but warned that it was “sceptical of these figures” due to numbers being possibly “manipulated for political narratives.”
A later post from Grok attributed this to a “programming error” and an “unauthorised change” that “caused Grok to question mainstream narratives, including the Holocaust’s 6 million death toll.”
In July, Musk’s xAI was forced to remove a series of “inappropriate” posts after Grok began praising Adolf Hitler, referring to itself as MechaHitler, and responding to user comments by repeating antisemitic claims.
“Since being made aware of the content, xAI has taken action to ban hate speech before Grok posts on X,” the post said.
Musk himself wrote on X in response to this incident that Grok was “too compliant to user prompts.” “Too eager to please and be manipulated, essentially. That is being addressed,” the tech billionaire wrote on X.