The social networking site has responded to the serious allegations made in a Channel 4 'Dispatches' documentary set to air on Tuesday (17.07.18), and confirmed the staff involved have been "retrained".
A spokeswoman told the BBC: "We haven't seen the footage but have seen the transcripts. And there is quite a lot of it that is against our policies and we are investigating... We have retrained the trainers at the company involved."
The undercover film sees a reporter working as a content moderator in the firm's largest centre in Dublin, where work has been outsourced to a company called CPL Resources since 2010.
The reporter is shown a disturbing image of a man punching and stamping on a toddler, which has been online since 2012 despite being marked "disturbing content".
Facebook claimed while the original video was removed, it was re-edited and re-shared repeatedly since it was taken down.
The company's vice-president of public policy Richard Allen has also fired back at the suggestion such content is left up for financial reasons.
He said: "Shocking content does not make us more money - that's just a misunderstanding of how the system works.
"People come to Facebook for a safe secure experience to share content with their family and friends.
"The vast majority of those two billion people would never dream of sharing content that, like that, to shock and offend people. And the vast majority of people don't want to see it."