In the hours after the El Paso, Texas, shooting on Aug 3, Mr Fredrick Brennan, founder of online message board 8chan - the site that had hosted the racist manifestos of the men responsible for the El Paso; Christchurch, New Zealand; and Poway, California, shootings - called for the site to be shut down.

In an interview with The New York Times, he said: "It's a complete negative to everybody except the users who are there. And you know what? It's a negative to them too. They just don't realise it."