A British teenage extremist has been jailed after his far-right videos were linked to two mass murders in the US.

Daniel Harris used an online platform called World Truth Videos to disseminate a “call to arms” for his violent racist beliefs, a court heard.

The 19-year-old from Glossop in Derbyshire was convicted of five counts of encouraging terrorism and one of possessing a 3D printer for the purposes of terrorism after a trial at Manchester Crown Court.

He was sentenced to 11-and-a-half years in jail, and a further three years on licence.

Prosecutors said US mass killer Payton Gendron was “encouraged and, in part, motivated to do what he did” by Harris.

Gendron murdered 10 black people in a mass shooting in Buffalo, New York, in May 2022 while livestreaming the attack. Within hours, Harris produced a video celebrating the killing spree.

Gendron, 19, had left a comment on one of Harris’s videos two months before the mass shooting, saying: “You are not alone my friend :)”.

The video included lessons to be learned from Brenton Tarrant, who livestreamed an attack in which he killed 51 people at mosques in New Zealand in March 2019.

Gendron had also taken an image from another of Harris’s videos and used it as the main image on his “manifesto”.

Prosecutor Joe Allman said Gendron was “inspired” by Harris’s material.

The British teenager also influenced Anderson Lee Aldrich, the only suspect in a shooting at a gay bar in Colorado, the court was told.

Aldrich, 22, allegedly killed five people during an indiscriminate firearms attack in Colorado Springs, in November last year – while Harris was on trial in the UK.

Aldrich – who is yet to enter pleas over the Colorado shooting – “accessed material” produced by Harris, Mr Allman said.

The prosecutor told the court one of Harris’s videos was posted on the “brother site” to a website with links to what appeared to be a livestream of Aldrich preparing to carry out the attacks.

Mr Allman said: “The Crown say it demonstrates that individuals of the greatest concern have accessed the material produced by Mr Harris.”

Read more:
What is ‘great replacement theory’ in Buffalo killer’s manifesto?
Buffalo shooting ‘fuelled by diet of hate’

Harris was described in court as an “influential online propagandist for a violent and deeply racist ideology”.

His videos glorified mass killings and were “tantamount to a call to arms to those who shared, or who could be persuaded to share Mr Harris’s world view,” Mr Allman said.

Under the pseudonym “BookAnon”, Harris’s videos “encouraged and gave instructions for carrying out acts of terror against those deemed not to be part of the white European race,” the court heard.

One video showed how to make an assault rifle using a 3D printer and when police raided Harris’s grandfather’s house, they found that he had begun making the parts himself.

‘Toxic rhetoric with untold influence’

After the teenager’s conviction, Detective Inspector Chris Brett said attempts were initially made to engage with Harris through the Prevent programme, which aims to stop people becoming terrorists.

“It soon became clear he was pretending to be deradicalised whilst encouraging terrorism online,” Mr Brett added.

“The threat he caused meant we had to act in order to ensure the safety of the wider public.”

Mr Brett said Harris “clearly demonstrated a disdain for law enforcement and public order, as well as an admiration for those who had committed atrocities in terrorist attacks overseas”.

“By posting these videos online, Harris’ toxic rhetoric could have had untold influence on countless people across the world – such actions will not be tolerated,” the senior officer said.

He added that officers made “the rather chilling discovery of attempts to make component parts of a firearm printed from his 3D printer” during a search, which “showed a clear intent to create a deadly weapon”.