https://www.theguardian.com/world/2019/mar/19/facebook-and-youtube-defend-response-to-christchurch-videos

YouTube says spread of videos of attack was ‘unprecedented in scale and speed’

YouTube and Facebook have defended themselves against accusations that they failed to act quickly enough in the wake of the Christchurch terror attack, arguing that their moderation is as good as possible given the number of videos uploaded.