Sarah Wynn-Williams, a former executive at Meta and author of an explosive insider account of her time at the social media giant testified before the Senate Judiciary Committee Tuesday, accusing the company of undermining national security and briefing China on U.S. artificial intelligence efforts in order to grow its business.

A former Meta official’s explosive insider account sold 60,000 copies in its first week and reached the top 10 on Amazon.

An insider account being billed as an “explosive” memoir about “seven critical years” at Facebook/Meta will be published next week.