Under-fire social network Facebook has finally come clean on its data practices, following an immensely high-profile fallout.

Facebook has suffered huge financial losses and a lack of public favour after it emerged that big data firm Cambridge Analytica scraped vast swathes of user data to deliver hyper-targeted content – usually in the hope of swinging elections. Crucially, Cambridge Analytica’s approach involved not only taking details from the individual being served the content, but also by reaching through their network of contacts to unethically harvest enormous swathes of personal information.

Now, following huge pressure from national governments across the world, Facebook has admitted its failings and acknowledged that these practices are likely to have been going on for years – affecting most users. In reference to Cambridge Analytica’s now-infamous data harvesting technique, an official publication from Facebook said: “We believe most people on Facebook could have had their public profile scraped in this way.”

Company chief Mark Zuckerberg expanded on this, saying how these activities may have been going on for longer than many people realise. In a journalist Q&A he said: “At some point during the last several years, someone has probably accessed your public information.”

Since that interview, Facebook has tried to put a number on the affected accounts – albeit without great success. The latest figure is 87 million people worldwide, although this has been increased from an original estimate of nearer 50 million. Of the current total, some 1.079 million accounts are said to be in the UK.

It’s thought that Cambridge Analytica was behind most, if not all, of the 87 million accounts which had data scraped.

In light of the breaches, Facebook’s chief technology officer Mike Schroepfer wrote a blog to say how the company would soon begin informing affected users that they might have had data accessed by third parties. He concluded with a promise that Facebook would now more properly restrict the data available to third party app developers.