The European Union (EU) has formally opened an investigation into X, the platform previously known as Twitter, to ensure it’s complying with the Digital Services Act (DSA) following Hamas’ attack on Israel in early October and subsequent Israeli air assault on Gaza. According to the request, this comes after “indications received by the Commission services of the alleged spreading of illegal content and disinformation, in particular the spreading of terrorist and violent content and hate speech.”

Earlier this week, EU Commissioner Thierry Breton sent a letter to X owner Elon Musk alleging that the platform is “being used to disseminate illegal content and disinformation in the EU.”

The EU is requesting that X provide information related to its investigation by October 18th. Investigators are reportedly asking X on what the company’s protocols are during crisis situations, according to the Financial Times. In his letter from earlier this week, Brenton noted the media has widely reported misleading imagery on X that includes previous armed conflicts as well as doctored ones.

The probe at X is the first under the new DSA, the Financial Times says. Under the law, tech giants like Meta, Google, and Amazon, which operate “very large online platforms” with millions of users, can be held liable for content that’s illegal in the EU. The commission could, in serious cases, impose fines of up to six percent of global revenue.

Brenton also sent a letter to Meta CEO Mark Zuckerberg on Wednesday, similarly urging his company to remove illegal content and “to be very vigilant to ensure strict compliance with the DSA rules.”