Hillary Clinton has questioned whether the data firm Cambridge Analytica helped the Russians meddle in the 2016 US election.

The former Democratic presidential candidate, who lost to Donald Trump, asked whether the Russians were “getting advice” from the company during the race.

The comments are made in the latest installment of a three-part investigation by Channel Four News into the firm, which helped Mr Trump’s online election campaign.

Cambridge Analytica is already facing scandal amid claims it harvested 50 million Facebook profiles and questions over the methods it uses in election campaigns across the world.

Mrs Clinton told Channel Four News: “The real question is how did the Russians know how to target their messages so precisely to undecided voters in Wisconsin or Michigan or Pennsylvania – that is really the nub of the question.

"So if they were getting advice from say Cambridge Analytica, or someone else, about ‘OK here are the 12 voters in this town in Wisconsin – that’s whose Facebook pages you need to be on to send these messages’ that indeed would be very disturbing.”