Brittany Kaiser, a former director at Cambridge Analytica, has been subpoenaed by special counsel Robert Mueller's investigation regarding possible links between President Trump's 2016 campaign and the Russian government, The Guardian reports.

The big picture: Kaiser is the second former employee from Cambridge Analytica, a now-shuttered, Trump-linked British analytics firm that harvested the data of millions of Facebook users, to be drawn into Mueller's probe. Kaiser told The Guardian that the subpoena came after a report that she'd visited WikiLeaks founder Julian Assange in February 2017 to discuss the results of the 2016 election while still employed by the firm.

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