Extreme online violence may be linked to rise of ‘0 to 100’ killers, experts say

Jonathan Hall, the government’s independent reviewer of terrorism legislation, said there was a ‘new threat cohort’. Photograph: Artur Marciniec/Alamy

The rise of “0 to 100” killers who go from watching torture, mutilation and beheading videos in their bedrooms to committing murder suggests there could be a link between extreme violence online and in real life, experts have said.

Criminal justice experts advocated a new approach, inspired by counter-terrorism, to identify an emerging type of murderer with no prior convictions, after cases such as Nicholas Prosper, who killed his mother and siblings and planned a primary school massacre.