The Federal Trade Commission has its complaint against TikTok to the Justice Department after a long-running investigation into the company’s privacy and security practices. “Our investigation found reason to believe that TikTok is violating or about to violate the FTC Act and the Children’s Online Privacy Protection Act (COPPA),” FTC Chair Lina Khan said in on X.

In a shared by the FTC, the regulator noted its investigation into TikTok after a 2019 privacy settlement related to Musical.ly, the app acquired by ByteDance that eventually became TikTok. The FTC “also investigated additional potential violations of COPPA and the FTC Act,” it said. It’s not clear exactly what the FTC turned up, though Politico earlier this year that the regulator was also looking into whether TikTok had misled users about whether their personal data was accessible to people in China.

The statement itself is a somewhat unusual move for the FTC, which acknowledged that it doesn’t typically publicize its referral decisions. It said it believed doing so in this case “was in the public interest.” The referral is likely to ramp up pressure on TikTok, which is also fighting a legal battle against the US government to avoid a . Lawmakers and other officials have alleged the app poses a national security threat due to its ties to China.

A TikTok spokesperson told Engadget in a statement that the company was “disappointed” with the FTC’s decision. “We’ve been working with the FTC for more than a year to address its concerns,” the spokesperson said. “We’re disappointed the agency is pursuing litigation instead of continuing to work with us on a reasonable solution. We strongly disagree with the FTC’s allegations, many of which relate to past events and practices that are factually inaccurate or have been addressed. We’re proud of and remain deeply committed to the work we’ve done to protect children and we will continue to update and improve our product.”