A teenager has been jailed for life with a minimum 25 years in prison for murdering a 14-year-old boy he groomed online.
Lewis Daynes, a computer engineer and avid gamer, had pleaded guilty to the murder of Breck Bednar, who was found with his throat slashed on 17 February last year.
Passing the sentence at Chelmsford Crown Court, Mrs Justice Cox said Daynes had exerted influence and control on the younger boy amounting to "grooming behaviour".
"The precise details of what happened in your flat are unclear and may never be known," she added. "I'm sure that this murder was driven by sadistic or sexual motivation."
Daynes, of Rosebery Road, Grays, previously denied murder but changed his plea on the day he was due to stand trial.
The 19-year-old’s lawyers told the court he did not accept that the murder of Breck had a “sexual and sadistic motivation", as the prosecution claimed, arguing his injuries had been inflicted from behind during a sexual act.
The boy was found fatally wounded at the flat in Grays, Essex, where he had gone to meet Daynes the day before.
Richard Whittam QC, a lawyer for the prosecution, said Daynes - who went by the online name EagleOneSix - befriended Breck over the internet and promised him "great wealth" from a fictional computer software business.
There was evidence of sexual activity between the two shortly before Breck, who was bound with duct tape on his wrists and ankles, was killed, he told the court.
Breck left home in Caterham, Surrey, the day before his death, telling his family he had arranged to meet a friend online.
The pair had chatted on an online gaming group that Daynes ran from his flat, where he lived alone after his mother left the country and his father asked the local authority to assume care.
A pizza was ordered and delivered that evening and the next contact with anyone outside the flat was the next day.
On the morning of 17 February, Daynes made a 999 call and claimed Breck had tried to take his own life and while struggling to restrain him, he had accidentally stabbed him.
During the call he spoke in a "cold" tone to give an "entirely false account", Mr Whittam added.
"Following the infliction of the fatal injury to Breck Bednar, Lewis Daynes disseminated images of his body to at least two people as well as making contact with a member of his online community to tell them that he was dead,” he told the court.
“He showered, then changed his clothes before calling the police.”
A post-mortem examination found Daynes had slashed his victim's throat. The nature of Breck's injuries meant death would have been “very rapid”, Mr Whittam said.
When police arrived, the murderer told them: “Look, I know he's dead, I stabbed the main artery in his neck.”
Shortly before the killing, the court was told that Daynes bought duct tape, condoms and syringes online.
Simon Mayo QC, mitigating, said he had Asperger's syndrome which “affects his ability to make sound judgments”.
Daynes did not accept that his behaviour had been sexual and sadistic, he added.
Mr Mayo said: “There is insufficient evidence for the court to conclude that there was a significant degree of premeditation and planning for murder.”
Breck’s family set up the Breck Bednar Memorial Foundation in the wake of his death, describing his as a “kind, well-liked, intelligent, thoughtful, independent, resourceful, responsible boy”.
The fund uses donations to fund young people wanting to study computing, Breck’s passion.
In a statement to the court, his father Barry said his son’s death had made him “a shell of a man, wracked with grief, consumed by sadness”.
His mother, Lorin LaFave, said she has since been unable to work because of the physical and emotional toll of their loss.
“I want Breck's story to save others from the evil in this world,” she added.
Daynes was previously arrested over claims he raped another teenager in 2011 but was released, it has emerged.
The judge lifted restrictions which prevented the reporting of five other counts the defendant denied, including four of sexual offences relating to another victim and one of possessing indecent images.
The matter has since been referred to the Independent Police Complaints Commission, which is investigating this along with other matters raised by the Bednar family.
Both Daynes and his alleged victim, who cannot be named for legal reasons, were 15 at the time of the incidents, which date back to between April 1 and July 10 2011.
Additional reporting by PA