Hours after going offline on Monday, social media start-up Parler filed a lawsuit in federal court accusing Amazon of antitrust violations and calling for an injunction to prevent that the tech giant is blocking access to cloud computing services.

Amazon told Parler over the weekend that the service would be discontinued because “a steady increase in violent content” on the site indicated the company did not have a reliable process to prevent it from violating Amazon’s Terms of Service. Amazon said it would make sure Parler’s data is preserved so it can be migrated to a new hosting provider.

Millions of people turned to Parler after Twitter and Facebook banned President Trump following the Capitol uprising last week. Apple and Google kicked Parler out of their app stores later this week, although users who had already downloaded the app could still use it. However, the app relied on Amazon’s cloud computing technology.

Parler’s complaint was dated Sunday before Amazon suspended Parler. However, the lawsuit wasn’t filed with the court until Monday.

In the lawsuit filed in the U.S. District Court for the Western Washington District, Parler accused Amazon of terminating, rather than just banning, its account – and said it should have been given 30 days notice. It has also been argued that Amazon violated antitrust laws by teaming up with Twitter, a large Amazon customer, to start Parler just as it was gaining broader appeal. It said it had 12 million users and “expects millions more this week given the growth in recent days.”

Parler did not provide direct evidence that Amazon and Twitter coordinated the response. Instead, it cited a December press release announcing a multi-year strategic partnership between Amazon and Twitter, and cited Twitter’s own challenges in monitoring the content.

Parler said losing Amazon’s services would be a “death knell,” although other platforms popular with far-right and conspiracy theorists, such as Gab and 8chan, have managed to bounce back after being canceled by hosting providers.

David J. Groesbeck, a sole intellectual property attorney based in Olympia, Washington, filed the lawsuit on behalf of Parler. Amazon didn’t respond to an instant request for comment.