Twitch is suing malicious users who took over the streaming platform’s Artifact category and flooded it with gore, pornography, copyrighted content, and even a video of a mass shooting. The lawsuit, which was filed on June 14 in a U.S. District Court in Northern California, is against unidentified streamers listed as “John and Jane Does 1 through 100.”

The lawsuit alleges trademark infringement, breach of contract, fraud, and unlawful use of the company’s platform. “Twitch’s success is due in part to the measures it has taken to create a safe and accessible community for its millions of users,” the lawsuit reads. “Twitch does not tolerate harassing or dangerous content, nudity and sexually explicit content or activities, or physical violence (including gore).”

In May, streamers noted that Artifact, the Dota 2 collectible card game, only had a small base of a few hundred viewers at any given time. This is notable for a game from a large studio like Valve, and once users noticed how quiet the section was, they began to stream copyrighted material, memes, and blatantly offensive content. The darker streams included footage of the Christchurch mosque shootings, self-mutilation, and hardcore pornography. Some banned users would simply use a new IP address with a fresh account to keep streaming the offensive content.

The lawsuit cites these attempts, reading:

Twitch took down the posts and banned the offending accounts, but the offensive video streams quickly reappeared using new accounts. It appears that Defendants use automated methods to create accounts and disseminate offensive material as well as to thwart Twitch’s safety mechanisms. Such methods are often referred to as “bots.” Defendants also use bots to artificially increase the popularity of the streams broadcasting the offensive conduct, making those streams more easily discoverable by users browsing Twitch. To protect the Twitch community, Twitch took the extremely disruptive step of disabling streaming for all newly created accounts for almost two days before imposing two-factor authentication for certain accounts. In response, Defendants sought to evade these steps using old accounts as well as accounts purchased from other users.

Twitch alleges in the lawsuit that the raid lasted so long because users coordinated off-site using channels like Discord and Weebly to continue broadcasting streams. Twitch suspended the ability for new users to stream and proactively banned any user in the Artifact section not streaming Artifact on May 28 in order to get the situation under control.

While it appears that Twitch does not know exactly who is responsible for the attack, the company says it will amend its lawsuit with the identified parties “if and when the legal names of such persons or entities become known.” The lawsuit may serve as a legal warning to other Twitch streamers who might attempt the same trick elsewhere on its site.

Twitch has provided a statement to Polygon via email, which reads:

Over the weekend of May 25, we became aware of a number of accounts engaging in a coordinated attack targeting the “Artifact” game directory to share content that grossly violates our terms of service. We worked with urgency to remove the offending content and suspend all accounts engaged in this behavior, and are taking measures to prevent this from happening on our service in the future. We take these violations extremely seriously — we are pursuing litigation to identify these bad actors, and will take all appropriate actions to protect our community.

You can read the lawsuit in full below.