蜜芽传媒

Thomas Mair, the killer of MP Jo Cox, was told by the trial judge there was no doubt the murder was committed to advance "violent white supremacist and exclusive nationalism".

Will Baldet, a coordinator for the government's anti-extremism Prevent scheme, says the internet is an echo chamber of unchallenged, extremist ideas and explains how best to tackle the problem.

(Image: Thomas Mair Credit: Reuters)