A 19-year-old British man who shot and killed his mother and two younger siblings and who wanted to carry out a high-profile school shooting has been told he will not be eligible for parole for at least 49 years.

At the sentencing hearing at Luton Crown Court on Wednesday, Justice Bobbie Cheema-Grubb said she had considered handing Nicholas Prosper a full life order in prison but opted against that given his age — he was 18 at the time of the shootings — and the fact that he had pleaded guilty,

Last month, Prosper admitted at a hearing to murdering his mother Juliana Falcon, 48, and his 13-year-old sister Giselle Prosper and 16-year-old brother Kyle Prosper at the apartment the family shared in Luton, Bedfordshire, on Sept. 13. He had also stabbed his brother more than 100 times

The judge said Prosper had wanted to emulate and outdo atrocities around the world, including the massacre at Sandy Hook Elementary School in Connecticut in Dec. 2012, when 26 people, mostly children were killed, and the mass shooting at Virginia Tech in April 2007 when 30 people were killed.

“Your ambition was notoriety,” she told Prosper, who had to be forced to come to the court to hear his fate. “You wanted to be known posthumously as the world’s most famous school shooter of the 21st century.”

The judge said Prosper's case featured many “recurrent themes” seen in school shootings around the world, including a sexual interest in children, a withdrawal into an online world, a lack of empathy towards victims and the selection of a “uniform” for the killings.

The court was told that Prosper, who had been unable to stay in education or hold down a job, had managed to forge a gun license and used it to buy a shotgun and 100 cartridges from a legitimate firearms dealer the day before the murders. His plan, the court was told, was to carry out a mass shooting at his old elementary school on Friday the 13th.

At about 5 a.m. that morning, Prosper carried out a test shot into a teddy bear in his bedroom. His mother had woken first, realizing something was “terribly wrong.” Prosper killed her, leaving a copy of the novel “How to Kill Your Family” on her legs, before shooting his sister as she hid under a table, and then stabbing and shooting his brother.

“The lives of your own mother and younger brother and sister were to be collateral damage on the way to fulfil your ambition,” the judge said.

With police swarming the area after the attack on his family was reported, Prosper flagged down police officers in a nearby street and showed them where he had hidden a loaded shotgun and 33 cartridges.

Bedfordshire Police Detective Superintendent Rob Hall read a statement on behalf of Prosper’s father Raymond Prosper, in which he said the deaths of his ex-partner Juliana and his son Kyle and daughter Giselle, had “much more meaning and importance”

“Their deaths and the fast response of Bedfordshire Police stopped any other family in the community going through the pain we have suffered,” he said.

Nicholas Prosper spent more than a year planning to kill his family and carry out a mass shooting at his former primary school.

Motivated purely by a desire for notoriety, he plotted to target at least 30 young children at St Joseph’s Catholic Primary School in Luton after murdering his mother Juliana Falcon and two siblings.

Bedfordshire Police said Prosper, then 18, made a booking at a shooting range in August 2023, 13 months before the harrowing attack on his family

There was nothing about his family background that seemed to suggest the defendant would go on to carry out the killings.

His parents separated when he was around eight or nine years old, but they were both in steady jobs and his father remained in close touch with the family.

At the time of his GCSEs in 2022, there were no concerns about Prosper – teachers described him as a quiet, introverted boy with a group of “geeky” friends who were interested in computers.

But teachers and relatives raised concerns about his mental health after something changed in the summer of that year, and when he started sixth form he stopped engaging with other people or doing his school work

Prosper admitted to the deputy head of the sixth form that he didn’t want to be there, but felt that he had to because his mum told him to, which made him angry.

The school decided Prosper was not suitable to continue with his A Levels by January 2023, and after he refused to engage with any support services he left the school that March.

He went on to work in Sainsbury’s stacking shelves from October to December 2023, but was sacked and became unemployed.

Prosper would spend hours online looking at extreme violent material, with a particular fixation on mass killings including school shootings such as the US Sandy Hook killings in 2012.

He also briefly looked at material linked to the Southport murders, as part of his general sinister obsession with mass killings.

The teenager was obsessed with a character in the Walking Dead video game, a young girl called Clementine, and posted rambling videos online about how he was the chosen one to protect her.

There was a suggestion that he developed a grudge against his sister for the way she played the game.

Prosper was not referred to the anti-extremism scheme Prevent, with the extent of his obsession only becoming clear after his devices were analysed by police in the wake of the murders.

After the booking at the shooting range, which he failed to attend, he became a member of Gun Trader UK in April 2024, and two months later started researching how to fake a firearms certificate and mass shootings.

By July he was carrying out detailed research into school start times and term dates at his former primary school.

At the end of August, Prosper managed to buy a gun after an initial failed attempt earlier in the month, meeting the legitimate seller in a car park on September 12, the day before the murders.

He paid above the asking price for gun to have it brought to him with additional cartridges.

Prosper managed to buy the shotgun and 100 cartridges from the seller by making a fake shotgun licence, and pretending to be interested in clay pigeon shooting.

When he was arrested, he repeatedly asked police officers if they had seen the licence, and while in a cell said: “Are you capable of what I have done?”

Prosper chose a specific black and yellow outfit for the day of the killings, on which he said he was unexpectedly disturbed by his mother while in his brother’s bedroom and had to carry out the murders earlier than he had planned.

He fled the flat just after 5.30am wearing the black and yellow uniform after the noise attracted the attention of neighbours, but left without his hat.

Prosper hid for two hours before police spotted him behaving strangely with one arm in the air, and he showed them where the gun and cartridges were hidden in nearby bushes.

On September 17 while in prison, he told a prison nurse that he had planned to carry out the school shooting.

There was a suggestion that he had planned to shoot himself after carrying out the murders and school shooting, with research found on his phone about how to commit suicide.

One document found showed his plan to kill his family, including a detailed map of their home, expressions of anger directed towards his mother and a drawing of him In his uniform.

A video filmed by Prosper in April 2024 showed him holding a piece of wood as a gun whilst wearing the uniform.

No other person was involved in his plans as he was an isolated character, but he had been engaging in chat rooms with like-minded people.

Prosper had also accessed information about assembling guns and making a pipe bomb, but there was no evidence he had tried to do so.

A number of Indecent images of children were found on his phone, but none were produced by himself.

Police said he has shown no empathy or remorse for his actions.

The incident did not meet the definition of terrorism as evidence suggested Prosper was not seeking to advance a political, religious, racial or ideological cause.

Earlier this month, the UK’s terror watchdog recommended the introduction of a new offence for lone individuals planning a mass killing that is not terrorism. (AP)

•Nicholas Prosper, 19, who murdered his mother and two siblings, and was plotting a primary school shooting. Bedfordshire Police/PA