Mark Zuckerberg on Wednesday said he was among the millions of Facebook users whose personal data was improperly obtained in the Cambridge Analytica scandal.

The reveal came amid a string of questions from Rep. Anna Eshoo during Zuckerbergs appearance before the House and Energy Committee on Wednesday.

Was your data sold to the malicious third parties? Your data? the California Democrat pressed.

The 33-year-old Facebook CEO responded with a resounding Yes, but his confidence faltered with the next question.

Are you willing to change your business model in the interest of protecting individual privacy? Eshoo asked in a follow-up.

Im not sure what that means, he replied.

Zuckerbergs appearance before the House Energy and Commerce Committee is focused on how Facebook handled the Cambridge Analytica scandal and what the Silicon Valley behemoth is doing to fix the problem.

The Britain-based political consultancy, which worked for Donald Trumps presidential campaign, obtained the data of as many as 87 million Facebook users in a bid to influence political elections.

“We didn’t take a broad enough view of our responsibility, and that was a big mistake,” Zuckerberg told House members Wednesday in his opening remarks.

“It was my mistake and I’m sorry. I started Facebook. I run it and I’m responsible for what happens here.”

The appearance comes less than 24 hours after the Facebook CEO was grilled for nearly five hours by 44 senators from the Judiciary and Commerce committees, who attacked the social media giants inability to protect users data and for failing to stop Russias use of the site as means to interfere in the 2016 presidential election.

The tech big-wig, poised and stone-faced on Tuesday, repeatedly apologized for Facebooks role in the data-mining scandal, adding that the company is reviewing the improper access third-party apps may have to data on the social network site.