European officials warned X on Tuesday that the company formerly known as Twitter appears to have been hosting misinformation and illegal content about the war between Hamas and Israel, in potential violation of the European Union’s signature content moderation law.

In a letter addressed to X owner Elon Musk, Thierry Breton, a top European commissioner, said X faces “very precise obligations regarding content moderation” and that the company’s handling of the unfolding conflict so far has raised doubts about its compliance.

As a platform subject to Europe’s Digital Services Act (DSA), X could face billions in fines if regulators conclude that violations have occurred. X didn’t immediately respond to a request for comment.