San Francisco, Dec 16 (IANS): Responding to criticism from all quarters over the spread of fake news, Facebook has asked its users to flag fake news stories which will be verified by third party fact-checkers.

According to media reports, Facebook was going to work with five fact-checking agencies - ABC News, AP, FactCheck.org, Politifact and Snopes.

Facebook believes in giving people a voice and that it could not become arbiters of truth itself, said Adam Mosseri, vice president of Facebook's News Feed.

The social networking platform was victim of fake news posts during the US presidential election in November.

"We've focused our efforts on the worst of the worst, on the clear hoaxes spread by spammers for their own gain, and on engaging both our community and third party organisations," Mosseri wrote in a statement on Thursday.

The proliferation of hoax and fake content on its platform apparently significantly affected public opinion during the recently-concluded US political campaign.

Facebook is now looking into four broader areas to address this.

"We're testing several ways to make it easier to report a hoax if you see one on Facebook, which you can do by clicking the upper right hand corner of a post.

"We've relied heavily on our community for help on this issue, and this can help us detect more fake new," Mosseri said.

"We've started a programme to work with third-party fact checking organisations that are signatories of Poynter's International Fact Checking Code of Principles.

"We'll use the reports from our community, along with other signals, to send stories to these organisations," he further added.

"If the fact-checking organisations identify a story as fake, it will get flagged as disputed and there will be a link to the corresponding article explaining why," Mosseri wrote.

Stories that were disputed may also appear lower in News Feed

"It will still be possible to share these stories, but you will see a warning that the story has been disputed as you share," he noted.

Once a story is flagged, it can't be made into an ad and promoted, either.

"We've found that if reading an article makes people significantly less likely to share it, that may be a sign that a story has misled people in some way. 

"We're going to test incorporating this signal into ranking, specifically for articles that are outliers, where people who read the article are significantly less likely to share it," the Facebook executive explained.

Facebook has found that a lot of fake news is financially motivated.

Spammers make money by masquerading as well-known news organisations, and posting hoaxes that get people to visit to their sites, which are often mostly ads.

"So we're doing several things to reduce the financial incentives. On the buying side, we've eliminated the ability to spoof domains, which will reduce the prevalence of sites that pretend to be real publications. 

"On the publisher side, we are analysing publisher sites to detect where policy enforcement actions might be necessary," Mosseri announced.

Facebook CEO Mark Zuckerberg recently said the company was committed to weed out "the worst of the worst".