An explosive leak of tens of thousands of documents from the defunct data firm Cambridge Analytica is set to expose the inner workings of the company that collapsed after the Observer revealed it had misappropriated 87 million Facebook profiles. More than 100,000 documents relating to work in 68 countries that will lay bare the global infrastructure of an operation used to manipulate voters on "an industrial scale" are set to be released over the next months. The documents were revealed to have come from Brittany Kaiser, an ex-Cambridge Analytica employee turned whistleblower, and to be the same ones subpoenaed by Robert Mueller's investigation into Russian interference in the 2016 presidential election. Kaiser ... decided to go public after last month's election in Britain. "It's so abundantly clear our electoral systems are wide open to abuse," she said. "I'm very fearful about what is going to happen in the US election later this year." Kaiser said the Facebook data scandal was part of a much bigger global operation that worked with governments, intelligence agencies, commercial companies and political campaigns to manipulate and influence people. The unpublished documents contain material that suggests the firm was working for a political party in Ukraine in 2017 even while under investigation as part of Mueller's inquiry and emails that Kaiser says describe how the firm helped develop a "sophisticated infrastructure of shell companies that were designed to funnel dark money into politics".