A British teenager who murdered three young girls at a Taylor Swift-themed dance event was obsessed with violence and genocide, prosecutors said on Thursday after the killer was removed for repeatedly interrupting his sentencing.

Axel Rudakubana, 18, will probably never be released, a judge ruled as he condemned the “extreme violence” of his knife attack on a dance class last year.

Axel Rudakubana has been taken out of the dock after complaining that he felt ill.