The filing was made in response to a TikTok lawsuit attempting to block the government’s ban. The Justice Department warned that the app’s algorithm and parent company ByteDance’s alleged ties to the Chinese government could be used for a “secret manipulation” campaign.

“Among other things, it would allow a foreign government to illicitly interfere with our political system and political discourse, including our elections…if, for example, the Chinese government were to determine that the outcome of a particular American election was sufficiently important to Chinese interests,” the filing said.

Under a law passed in April, TikTok has until January 2025 to find a new owner or it will be banned in the U.S.

The company is suing to have that law overturned, saying it violates the company’s First Amendment rights. The Justice Department disputed those claims.

“The statute is aimed at national-security concerns unique to TikTok’s connection to a hostile foreign power, not at any suppression of protected speech,” officials wrote.

TikTok has been a concern to the U.S. government for much of the past five years, given ByteDance’s China ties. Critics are worried about the Chinese government potentially being able to influence users via the site’s algorithm and the troves of data the app collects about U.S. users.

The algorithm, U.S. officials wrote, “can be manually manipulated, and its location in China would permit the Chinese government to covertly control the algorithm—and thus secretly shape the content that American users receive.”