Nicholas Prosper gave an emotionless “no comment” interview to police after he was arrested for the murders of his mother, Juliana Falcon, 48, and his younger siblings, Giselle, 13, and Kyle, 16, in Luton in September 2024.
The 19-year-old, who wanted to carry out a high-profile school shooting, was jailed for life with a minimum of 49 years at Luton Crown Court on Wednesday, 19 March.
A judge told him he is highly dangerous, and that he will never be released unless experts deem he no longer poses a risk to society.
Justice Bobbie Cheema-Grubb said she had considered handing Nicholas Prosper a full life sentence 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.