Facebook could face yet another investigation this time for its aggressive behavior against Snapchat.

According to the Wall Street Journal, Snapchat is handing over a trove of documents to the Federal Trade Commission (FTC) detailing Facebook’s efforts to stifle its business.

According to the report, the documents accuse Facebook of preventing Snapchat-related content from trending on Instagram’s Explore page and blocking searches of Snapchat-related terms. Snapchat also says Instagram threatened to take away users’ verified status if they posted Snapchat links on their profile.

Neither Facebook nor Snapchat responded to requests for comment.

The FTC is also investigating Facebook for copying key features from their rivals after the company failed to acquire them, which happened with Snapchat and Foursquare.

The social media giant is under four separate antitrust investigations, including the one being conducted by the FTC. The Department of Justice, Congress and a bipartisan group of state attorneys general are each probing the company.