Public prosecutors in Paris launched an investigation after Grok appeared to verify false claims made on X by a French neo-Nazi previously convicted of Holocaust denial offences.

Musk has encouraged users of his social media platform to use Grok as a fact-checking tool, though its output is frequently racist and inaccurate.

Grok’s post denying the use of gas chambers for the extermination of Jews remained online for three days and was viewed more than a million times before it was removed, The Guardian reports.

The Paris prosecutor’s office said “Holocaust-denying comments shared by the artificial intelligence, Grok” had been added to the scope of an existing investigation into foreign political interference by X.

A statement posted from Grok’s X account said: “We are aware of recent posts made by Grok and are actively working to remove the inappropriate posts.

“Since being made aware of the content, xAI has taken action to ban hate speech before Grok posts on X.

“xAI is training only truth-seeking and thanks to the millions of users on X, we are able to quickly identify and update the model where training could be improved.”