Pressure is mounting on Facebook to explain how a British firm used data from 50 million of its users without permission.
Boss Mark Zuckerberg has been asked to appear before the British and European parliaments.
Meanwhile, a warrant is being sought to search the premises of Cambridge Analytica - which denies accusations it used the data to target ads at voters.
The backlash against Facebook over its handling of personal data has seen a co-founder of WhatsApp appear to back calls for users to delete their profiles.
Brian Acton tweeted: "It is time. #deletefacebook" as the hashtag trended amid growing outrage over the social media giant's links to controversial British data firm Cambridge Analytica (CA).
Along with WhatsApp co-founder Jan Koum, Acton sold the app to Facebook for $19 billion (€15.4 billion) in 2014.
CA was suspended from the social media giant last week after it emerged that data on 50 million users had not been destroyed as agreed.
Damian Collins, UK chairman of the Digital, Culture, Media and Sport Committee wrote to Mr Zuckerberg yesterday requesting that the firm explains the "catastrophic" failure.
The data firm suspended its chief executive, Alexander Nix, after recordings emerged of him making a series of controversial claims, including boasts that CA had a pivotal role in the election of Donald Trump.
In a statement, the CA board said that Mr Nix had been suspended "with immediate effect, pending a full, independent investigation".
It said comments by Mr Nix recorded in secret filming by Channel 4 News and "other allegations" did not represent "the values or operations of the firm" and that his suspension "reflects the seriousness with which we view this violation".
Every interaction on Facebook generates data, while users volunteer some information in their profile like their hometown and birthday.
Other data could be about interests gleaned from publicly "liking" content, while Facebook also knows where users log on to its site from, the device they use, and which ads they click on.
Users can see what info is shared with any app, and there are options to delete, limit the information each app can access and remove info collected by the app.
Deleting an app may still allow the developer to retain some of a user's personal information.
WhatsApp has itself been the subject of criticism by Governments and security services in recent years for providing a means for criminals and terrorists to evade surveillance.
In February, Mr Acton launched the Signal Foundation, a nonprofit developing technology that "protects free expression and enables secure global communication".