Facebook founder Mark Zuckerberg has admitted that the social network “made mistakes” that led to millions of Facebook users having their data exploited by a political consultancy.Cambridge Analytica is accused of improperly using the data on behalf of political clients. In a statement Zuckerberg said a “breach of trust” had occurred. In a later interview with CNN he said he was “really sorry”, and pledged to take action against “rogue apps”.