Three teenagers who killed a promising young rapper at a 16th birthday party have been detained, as a judge warned of the dangers of a “plague of knife crime”.

Shane Cunningham fatally stabbed Mikey Roynon, 16, in the neck with a large knife during a house party in Bath, Somerset, in June last year.

The 16-year-old was convicted of murder while his two friends, Cartel Bushnell and Leo Knight, were found guilty of Mikey’s manslaughter, after a trial at Bristol Crown Court.

Cunningham was given a life sentence and ordered to serve a minimum of 16 years’ detention, while Bushnell and Knight, both 16, received sentences of nine years and nine-and-a-half years youth detention respectively.

Mr Justice Saini ruled that all three could be identified, despite their age, after an application by the PA news agency.

Passing sentence, the judge said Mikey’s family had suffered a “loss which is unimaginable”.

“Mikey had a bright musical career ahead of him and although he had faced a number of challenges in his short life, his future looked promising,” the judge said.

“As I said at the trial, Bristol and its surrounding areas are in the middle of a plague of knife crime.

“The plague has continued since this trial finished. The lives of young boys who carry knives continue to be taken at the hands of other boys who carry knives.

“Those who carry knives are themselves the most likely to be killed with a knife.

“I should make it clear to you Shane, Cartel and Leo, that I do not sentence you on the basis that you have any responsibility for that appalling situation.”

The judge said he accepted the defendants had not gone to the party expecting trouble but were each armed with “big knives” hidden in their clothing.

“How you each got hold of these horrendous and unlawful weapons and why you took them to the party will never be known,” the judge said.

“As I have said, I do not think that you went to the party to fight with anyone. But it is clear that you took the weapons with you for fighting with and for injuring people, if any violence took place.”

About 70 young people were at the gathering in Eastfield Avenue, Weston, when Mikey was fatally injured.

“I am satisfied that many of the other boys, including some boys from Bristol, went to the party armed with substantial knives,” the judge said.

“I am also sure that Mikey had a knife. Whether he took it with him to the party, or whether someone gave it to him, cannot be known.”

The judge said the three defendants had their knives out, which may have been a “reaction” to the other group having weapons.

“It was also an offensive act – you were ready to fight and use your knives,” he said.

“Mikey drew a knife and struck towards you, Cartel. It was at around this time that Shane stabbed Mikey in the neck.

“These were fast-moving events but the jury on their verdicts rejected your cases that there was any element of self-defence in what each of you did.”

Mikey was left bleeding heavily from a wound to his neck and collapsed on the driveway of the venue.

Police, paramedics and doctors were quickly at the scene but could not save Mikey’s life.

The defendants, all from Devizes, Wiltshire, left the scene and later disposed of their weapons. Two were recovered by the police.

They all denied a charge of murder. Cunningham was found guilty, while Bushnell and Knight were acquitted of murder but convicted of manslaughter.

Cunningham and Bushnell had pleaded guilty to possessing a bladed article, which Knight was convicted of after trial.

Ray Tully KC, representing Cunningham, said the consequences of carrying knives were clear, with his client facing a life sentence.

“On the facts he was not the first person to use a knife that night and he wasn’t the first person to strike out with a knife,” he added.

Anna Vigars KC, representing Bushnell, said: “It is sadly the hard truth that very many young people, particularly boys, carry knives.”

Mohammed Nawaz KC, representing Knight, said the court could not be sure on the evidence that his client had produced a knife before the incident began.

“There is no evidence that he instigated the incident that led to Mikey’s death,” he added.

In victim impact statements, Mikey’s mother, Hayley Ryall, said “my life changed forever” the day her son died.

“Every morning I wake up and it hurts as much as the last morning,” she said.

“I keep having awful dreams that Mikey is lost and I’m looking for him, but even the awful dreams are better than waking up to reality.

“At least in my dreams he is somewhere, whereas in reality he is gone.”

She added: “Life will not be normal again.”

Mikey’s father, Michael Roynon, described the day of his son’s death as a “living nightmare”.

“Never would I imagine when I last said goodbye to him, it would be the last time I would see him alive,” he said.

“I just feel so tortured from the loss of my boy.

“Nothing will bring Mikey back and as a dad losing my only son, I feel like I have a life sentence and will have to live with this forever.

“I can only hope that as time goes on, I feel less wounded and can find a way to rebuild my heart and life which has been shattered by Mikey’s death.”

Detective Inspector Mark Newbury, the senior investigating officer, said: “Knife crime is a disease which leaves a horrifying and long-lasting mark on everyone it affects, it’s a national problem which isn’t limited to specific towns or cities and we must come together as a society to tackle it.”