Facebook apologized for a data breach. CEO Mark Zuckerberg took out full- ads in newspapers. He was being criticized for his response to of the breach. A group of called Cambridge Analytica is accused of using on up to 50 million users to benefit Donald Trump's presidential . Zuckerberg said: "This was a breach of , and I am ....We're now taking to make sure this doesn't happen ."
Mr Zuckerberg said Facebook should have done to protect data. Facebook was warned about its data protection in 2011. Mr Zuckerberg outlined Facebook would do. He said: "We're investigating every app that had access to amounts of data...We expect there are . The of Facebook fell by $75 billion this week. Many users have abandoned Facebook , in calls to #deletefacebook.