Several fake election stories went viral on Facebook during the US presidential campaign iStock

Fake news stories about the US presidential race generated more engagements on Facebook than real stories during the closing months of the election, according to a report by BuzzFeed news. Data analysed by the website revealed that made-up articles from hoax websites and hyperpartisan blogs received more likes, shares and comments on Facebook than the best-performing election stories from major news outlets.

During the final three months of the US presidential campaign, the 20 best-performing fake election stories accrued more than 8.7 million interactions on Facebook, while the top 20 articles from major publications such as the Washington Post, New York Times and NBC News generated 7.4 million interactions.

The top-performing falsified stories included a report that Hillary Clinton sold weapons to ISIS, a hoax claiming that the Pope had endorsed Donald Trump and another story claiming that an FBI agent investigating Clinton's use of a private email server had been found dead.

The hoax regarding the Pope's endorsement of Trump generated 960,000 reactions, shares and comments on Facebook and outperformed the top-performing election stories from the Washington Post, Huffington Post, CNN and the New York Times, Buzzfeed found.

BuzzFeed's analysis found that top-performing election coverage by mainstream news outlets "easily outpaced" fake election news on Facebook up until the final three months of the campaign, at which point engagement with fake content skyrocketed past stories from major news outlets. The large majority of viral fake news stories were in favour of Trump.

Facebook has denied accusations that it helped swing the vote in favour of Trump by allowing fake new articles to proliferate unchecked on the website, with Mark Zuckerberg branding the claims "a pretty crazy idea". He also suggested that more than 99% of the content people viewed on Facebook was authentic and said the "small amount" of fake news on the social media platform could not have influence the outcome of the election.

Yet some Facebook employees have rebutted this claim, telling BuzzFeed that fabricated content "ran wild" during the presidential campaign. Staff are now reported to have launched a clandestine internal investigation into the part Facebook played in promoting fake election coverage.