A teenager who stabbed three young girls at a Taylor Swift-themed dance class in England has been sentenced to more than 50 years in prison.

Six months after a teenage attacker stabbed three girls to death at a children’s dance class in England, new details about his background have sparked questions about how authorities repeatedly failed to spot the threat he posed.

A 26-year-old man pleaded guilty Wednesday to the murder of a mother and two of her daughters at their family home just north of London last year, in an attack that involved a crossbow and a knife. Prosecutors said Kyle Clifford killed his 25-year-old ex-girlfriend Louise Hunt and her 28-year-old sister Hannah Hunt with a crossbow before stabbing their mother,

Prime Minister Keir Starmer says the killing of three young girls at a Taylor Swift-themed dance class must lead to “fundamental change” in how the British state protects citizens.

Axel Rudakubana admitted a total of 16 charges, including the three counts of murder, 10 counts of attempted murder and one count of possessing a blade.

A British teen pleaded guilty Monday to murdering three girls and attempting to kill 10 other people in what a prosecutor said was a “meticulously planned” stabbing rampage at a Taylor Swift-themed dance class in England last summer.

Judge Mr Justice Goose ordered Axel Rudakubana to be removed from the dock shortly after the start of the sentencing hearing.