Facebook Mark Zuckerberg apologized for the data that was revealed last week. Mr Zuckerberg took out full-page in broadsheet newspapers in the UK and US to make his for the data privacy . Zuckerberg was being criticized for being too slow to respond to the . Personal data on up to 50 million users was used by a U.S. political called Cambridge Analytica. This company is accused of using the leaked data to benefit Donald Trump's 2016 presidential . Zuckerberg said: "This was a breach of trust, and I am sorry.... We're now taking to make sure this doesn't happen again." The apology made no of Cambridge Analytica.
Mr Zuckerberg acknowledged that Facebook could and should have done to protect user and to stop it being exploited. Reports are now circulating that Facebook was warned its data was too weak back in 2011. Mr Zuckerberg outlined the actions Facebook would take going . He said: "We're investigating every single app that had access to amounts of data before we fixed . We expect there are others. And when we find them, we will ban them and tell affected." The value of Facebook has fallen by $75 billion this week; Zuckerberg's fell by $10 billion. There has also been a in users abandoning their Facebook pages, in online to #deletefacebook.