Axel Rudakubana has been sentenced to a minimum of 52 years in jail for the murder of three girls at a dance class in Southport last July, and the attempted murder of 10 other people.
Mr Justice Goose said the sentences will run concurrently, meaning they will be served at the same time.
He concludes that it is highly likely Rudakubana will never be released.
Families in court held hands and hugged as the sentence was read in court, with some heard taking an audible breath as it was announced.
Relatives held hands and hugged each other but remained silent as the judge announced the remaining sentences.
Earlier, the court heard harrowing details of the attack, including how Rudakubana arrived in a taxi booked under a fake name, how an instructor told the children to run away, and how a local man was injured as he tried to help.
While in custody after the attacks, Rudakubana said: “I don’t care, I’m feeling neutral… literally, such a good thing those kids are dead”.
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