Facebook is facing an historic crisis.

Revelations brought to light from whistleblower Frances Haugen, a former data scientist at Facebook, has led to what may be the most threatening scandal in the social media company’s history.

There is a pushback from Facebook on U.S. Senate testimony from Haugen who claims the company knows its platforms are used to spread hate, violence and misinformation and has done nothing to prevent it from happening.

“Facebook’s products harm children, stoke division and weaken our democracy,” Haugen told the U.S. Senate Commerce Subcommittee on Consumer Protection, “The company’s leadership knows how to make Facebook and Instagram safer, but won’t make the necessary changes because they’ve put their astronomical profits before people. Congressional action is needed. We won’t solve this crisis without your help.”

Frances Haugen worked in the social media giant’s civic integrity division and smuggled thousands of internal documents out of the company before leaving earlier this year.

But Monica Bickert, who is Facebook’s Vice President of Content Policy says Haugen wasn’t as involved as she claims.

“You know, she didn’t work on these issues at Facebook and I think she’s mis-characterized a lot of the documents that she stole,” Bickert rebutted in a media interview.

Later on Tuesday, Facebook founder and CEO Mark Zuckerberg broke his silence on the unfolding crisis in a memo posted to his Facebook page, claiming that Haugen’s accusations “don’t make sense” and that the company cared “deeply” about safety issues.

Sen. Richard Blumenthal (D-CT) said Tuesday the world’s largest social media company is facing a “big tobacco, jaw dropping moment of truth” as a massive cache of internal whistleblower documents show Facebook put profits ahead of the safety of children, when it knew it was causing harm.

He introduced a Senate Commerce subcommittee hearing focused on testimony by former Facebook executive Frances Haugen by thanking her for “standing up to one of the most powerful, implacable corporations in the world.”