Federal prosecutors in the US are now probing whether top executives of Facebook, mired in data breaches, were aware of data harvesting by the British political consulting firm Cambridge Analytica.

According to a report in The Guardian on Sunday, federal prosecutors' investigation claims that the social media giant has "covered up" the extent of its relationship with Cambridge Analytica.

"The Observer has also learned of claims that a meeting was hosted at the office of Facebook board member and confidant of its CEO Mark Zuckerberg, Christopher Wylie, the Cambridge Analytica whistleblower, in the summer of 2016 just as the data firm started working for the Trump campaign," said the report.

Facebook has been denying for long that it was aware of data harvesting of nearly 87 million users by the British political consultancy firm, who were targeted with political bias via Facebook posts in the 2016 US Presidential election.

A Facebook spokesperson told The New York Times: "We are co-operating with investigators and take these probes seriously."

In December 2018, Washington DC's top prosecutor sued Facebook in a first significant move to punish the firm for its role in the Cambridge Analytica scandal.

District of Columbia Attorney General Karl Racine filed the lawsuit that accused Facebook of allowing wholesale scraping of personal data on tens of millions of users.

Facebook is also being probed by the US Securities and Exchange Commission, the Federal Trade Commission and the Department of Justice.

In the UK, the company was fined 500,000 pounds - the maximum fine the British data regulator can impose - over the Cambridge Analytica scandal.