LOSANGELES:- Graphic videos showing children being abused remain on Facebook despite numerous requests to have them removed, an undercover film has suggested. Moderators also do not remove posts that violate hate speech and routinely ignore posts from children who may be under-age. The allegations are made in a Channel 4 Dispatches documentary. Facebook said mistakes had been made and the staff involved had been “retrained”. “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,” a spokeswoman told the BBC.