MENLO PARK (CBS SF/AP) -- Facebook is sending out millions of notifications to users whose data was shared with Cambridge Analytica. The messages will begin appearing Monday on users' news feeds.
The social media mega-giant estimates 87 million users are affected.
The data harvested includes users names, birthdates, lists of every Facebook page ever liked or downloaded and that of all of their friends, according to the New York Times.
Facebook founder, Mark Zuckerberg said as many as 146 million people may have received information from a Russian agency that's accused of orchestrating much of the cyber-meddling in the 2016 presidential election.
The Facebook CEO says his company found about 470 accounts and pages linked to the St. Petersburg-based Internet Research Agency, which generated around 80,000 Facebook posts over roughly a two-year period.
Zuckerberg says most of the people -- roughly 126 million -- "may have been served content" from a Facebook page linked to the Russian agency. Another 20 million "were likely served" on Instagram.
He is set to appear before a joint hearing of the Senate Judiciary and Commerce committees on Tuesday afternoon followed by a House Energy and Commerce Committee hearing on Wednesday morning.
The Trump administration last month hit Internet Research Agency employees with financial sanctions. Special Counsel Robert Mueller had earlier indicted these employees for seeking to conduct "information warfare" against the U.S.
© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.
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