Thirteen states and the District of Columbia sued TikTok on Tuesday, accusing the company of creating an intentionally addictive app that harmed children and teenagers while making false claims to the public about its commitment to safety.

In separate lawsuits, a bipartisan group of attorneys general cited internal company documents to paint a picture of a multibillion-dollar company that knowingly contributed to a mental health crisis among American teenagers to maximize its advertising revenue. They said that TikTok, which is owned by Chinese company ByteDance, had relentlessly designed features to prompt heavy, compulsive use of TikTok and that many children were using the app late at night when they would otherwise have been asleep.

TikTok “knew the harms to children,” Rob Bonta, the Democratic attorney general of California, said in an interview. “They chose addiction and more use and more eyeballs and more mental and physical harm for our young people in order to get profits — it’s really that simple.”

“Young addiction is a key and central pillar to TikTok’s business model,” Bonta said Tuesday in San Francisco, adding that the company has been very successful at it. Bonta said TikTok has 16 million users in California, many of whom use it multiple hours every day.

The lawsuit alleges that TikTok is engaged in false advertising and unfair business practices. But Bonta criticized three features he called “manipulative, addictive, harmful” to kids. Beauty filters fuel mental and physical health disorders and TikTok knows that this harms kids, he said, while auto play and infinite scroll features make users lose track of time and push notifications to pull them back in, interrupting school, sleep and activities.

Bonta said all three of his kids use TikTok, and that parents in the state and U.S. are “rightfully worried” about the effects of using TikTok.

“I know our parents are worried,” Bonta said. “I’m worried. I’m also fed up.”

The lawsuits add to a rapidly expanding list of challenges for TikTok in the United States, which now has 170 million monthly U.S. users. A federal law passed in April calls for the app to be banned in the United States as of January unless it is sold. A federal lawsuit against the company in August also claimed that TikTok allowed children to open accounts, gathered information about them and made it difficult for their parents to delete the accounts.

TikTok strongly disagreed with the claims in the lawsuits and that it provided “robust” safeguards for young users.

“We’re proud of and remain deeply committed to the work we’ve done to protect teens, and we will continue to update and improve our product,” Alex Haurek, a spokesperson said in a statement. He added that TikTok had tried to work with the attorneys general for more than two years and found the lawsuits “disappointing.”

The attorneys general say that TikTok has misled users about its so-called 60-minute screen time limits for young people and other features that promise to curate the videos that they see.

The states have also taken umbrage with beauty filters on TikTok — technology that alters the faces of users — saying that they are especially problematic for young women. New York’s lawsuit cited a study saying that 50% of girls believe they do not look good without editing. “TikTok is well aware that its beauty filter features lead to unhealthy, negative mental and physical disorders” but chooses to keep them on the platform anyway, the state said.

The action is similar to a set of lawsuits that states brought against Meta in the last year, accusing the company of unfairly hooking teenagers and children to Instagram and Facebook while it publicly downplayed the hazards of the sites.

Staff writer Grant Stringer contributed to this report.