Facebook has suspended Cambridge Analytica as it investigates whether the Donald Trump-connected data analysis firm failed to delete personal data that the social network says it improperly obtained from hundreds of thousands of users.

Facebook announced the suspension of the accounts of Cambridge Analytica and its parent company late Friday after being tipped off that the user data the analysis firm had received from a researcher — who had obtained it from a personality quiz app accessed through Facebook — was not destroyed as promised.

The suspension comes as Facebook continues to deal with the fallout from the 2016 election, when campaigns and foreign influence operations used social media in unprecedented ways to sway voters. Cambridge Analytica, backed by top Trump donor and hedge-fund billionaire Robert Mercer, claims it can predict how people will vote based on the 5,000 pieces of data it collects on nearly every American adult combined with the results of thousands of personality surveys. Enlisted by the Trump campaign, it touted its role in swinging the 2016 presidential election.

Facebook said a psychology professor legitimately gained access to the personal data of Facebook users while working on a personality prediction app, but the researcher violated Facebook’s rules by passing it on to Cambridge Analytica, Facebook says.

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