Facebook said today that it had begun "fact-checking" photos and videos to reduce the hoaxes and false news stories that have plagued the world's largest social media network. Reuters reports: The fact-checking began on Wednesday in France with assistance from the news organization AFP and will soon expand to more countries and partners, Tessa Lyons, a product manager at Facebook, said in a briefing with reporters. Lyons did not say what criteria Facebook or AFP would use to evaluate photos and videos, or how much a photo could be edited or doctored before it is ruled fake. The project is part of "efforts to fight false news around elections," she said. Facebook has tried other ways to stem the spread of fake news. It has used third-party fact-checkers to identify them, and then given such stories less prominence in the Facebook News Feed when people share links to them.