Facebook initially estimated information from about 50 million users was improperly collected by political research firm Cambridge Analytica, but company officials upped the count April 4 to 87 million, according to The New York Times.
Facebook announced March 16 that Cambridge Analytica harvested data from user profiles for the benefit of President Donald Trump's 2016 election campaign. The company licensed data from no more than 30 million user profiles, but Facebook CEO Mark Zuckerberg said Cambridge Analytica actually acquired information from nearly 87 million users.
"It's clear now that we didn't focus enough on preventing abuse," Mr. Zuckerberg said, according to The New York Times. "We didn't take a broad enough view of what our responsibility is. That was a huge mistake, and it was my mistake."
Facebook Chief Technology Officer Mike Schroepfer said the company is taking steps to increase security practices by tightening information access for third-party apps.
Mr. Zuckerberg is set to testify before the House Energy and Commerce Committee April 11 regarding Cambridge Analytica's use of profile information.
"This hearing will be an important opportunity to shed light on critical consumer data privacy issues," said Reps. Greg Walden, R-Ore., and Frank Pallone, D-N.J.