Meta whistleblower Sarah Wynn-Williams told senators in testimony Wednesday on Capitol Hill that the social media company worked “hand in glove” with the Chinese government to censor its platforms, according to her written remarks obtained by CBS News.

Wynn-Williams began working at Meta, then known as Facebook, as the director of Global Public Policy in 2011. In her almost seven years at Meta, Wynn-Williams says she witnessed the company provide “custom built censorship tools” for the Chinese Communist Party, allow user data, including that of American users, to be accessed by the CCP, and remove the account of a Chinese dissident.

Wynn-Williams alleged in her written remarks that Meta’s artificial intelligence model known as “Llama” was used to help DeepSeek. DeepSeek is a Chinese AI company that sent shockwaves through the American technology industry earlier this year when its AI model was shown to be competitive with OpenAI’s ChatGPT at a fraction of the cost.

In response, a Meta spokesperson called Wynn-Williams’ tesimony “divorced from reality and riddled with false claims.”

“While Mark Zuckerberg himself was public about our interest in offering our services in China and details were widely reported beginning over a decade ago, the fact is this: we do not operate our services in China today,” Meta said in a statement. 

Republican Sen. Josh Hawley of Missouri, who chairs the Senate Judiciary Subcommittee on Crime and Counterterrorism, announced the hearing last week.

Meta, which changed its name from Facebook in 2021, operates some of the most popular social media platforms in the United States, including its previous namesake Facebook as well as Instagram, WhatsApp and Threads. 

The hearing comes as Washington takes a more aggressive posture toward China and its growing threat to American economic interests and national security. The Trump administration is set to implement 104% tariffs on goods from China in early hours Wednesday. In 2023, the House of Representatives created the Select Committee on Strategic Competition between the United States and the Chinese Communist Party to investigate China’s challenge to American global power.

In March, Wynn-Williams published a memoir called “Careless People: A Cautionary Tale of Power, Greed and Lost Idealism” about her time at Meta.