A judge has jailed a teenager for life after deciding it was "only a matter of time" before the loner carried out a massacre at his former college.
Liam Lyburd, 19, had amassed a fearsome arsenal of pipe bombs, a Glock semi-automatic pistol, 94 expanding bullets, a machete and a "kill bag", and planned revenge on Newcastle College after it kicked him out for bad behaviour.
His plot to go on a murderous spree was thwarted by a concerned Facebook contact who saw his online rants and alerted the police.
Judge Paul Sloan QC jailed him for life with a minimum term of eight years but said it could be "a very long time" before he was considered safe enough for release.
Lyburd did not react when the judge passed sentence and told him: "Hearing the evidence in this case was, to say the least, a chilling experience.
"Your emotional coldness and detachment and your lack of empathy to others was self-evident."
Judge Sloan told Lyburd that, if that person had not tipped off the police, "it was only a matter of time before you would have put your plan into action".
After being thrown out of college in 2012, Lyburd retreated into a reclusive online world, rarely leaving his bedroom, and amassed his arsenal using the Dark Web to buy illicit items.
He was jailed at Newcastle Crown Court having admitted possessing the firearms and bombs and being found guilty of having them with intent to endanger life.
When police raided his home last November, they found the cache of weapons, the bag containing his overalls, mask, boots and pipe bombs, and incriminating evidence on his laptop.
A computer specialist recovered a deleted file from his computer in which he wrote about getting vengeance on the college.
It said: "You people ruined my whole life, don't expect me to show mercy today. No-one disrespects me and gets away with it.
"I'll teach you people a little lesson on respect with my 9mm jacketed hollow points. It's time for extreme civil disobedience.
"Fantasy will become reality today for sure. Where the mind goes the body will follow and, yes, people will die, there's no question about that."
As Lyburd was taken away by police, he laughed and told officers they had saved lives, adding "I need help."
They found webcam pictures he took of himself dressed for combat, armed with a Glock and brandishing a knife.
The estate where he lived with his mother and sister near Newcastle United's stadium was cordoned off for days while police carried out searches.
Psychiatrists could not specify a time when he would cease to be a danger to the public, said Nick Dry, prosecuting.
While he has been in jail awaiting sentence, Lyburd has repeated his threats to shoot people, he added.
Anne Richardson, defending, said that comment was a calculated attempt to get out of sharing a cell.
After being isolated in his bedroom for several years, he has "struggled" with being in close proximity with others, she added.
Lyburd had no "terrorist ideation", Miss Richardson said, and no links to any group or cause.
He was immature, she said, and had smiled for the cameras when he was led into the magistrates' court for his first hearing.
Miss Richardson said he had told officials since then: "I did enjoy the attention but now I am just very embarrassed."
She urged the judge to hold back from a life sentence, saying a man of just 19 would find it "abhorrent".
Psychiatric reports found that Lyburd had no acute mental illness, although one found he had schizoid traits, revealed by his emotional coldness, his detachment and lack of friends, Judge Sloan said.
He immersed himself in a cyber world and developed a love of violent films and an obsession with the Batman villain the Joker.
He had a "pent-up anger and a search for vengeance which the cyber world allowed him to achieve", Judge Sloan said.
These traits did not stop him from understanding what he was doing, he added.