Hashem Abedi, the younger brother and accomplice of the bomber who carried out the 2017 attack on the Manchester Arena following an Ariana Grande concert, has been sentenced to 55 years in prison, the BBC reports. In March, a jury found Abedi guilty of 22 counts of murder, attempted murder, and conspiring to cause explosions after he was extradited back to the UK from Libya to stand trial.

Abedi spent months planning and stockpiling deadly materials with his brother Salman, who was killed after detonating the bomb. “The stark reality is, these were atrocious crimes,” judge Jeremy Baker told the court. “Large in scale, deadly in intent, appalling in their consequences. The despair and desolation of the bereaved families has been palpable.” Abedi, 23, refused to leave his cell for the sentencing.

Abedi will spend 55 years in prison before he can be considered for parole and “may never be released,” Baker said. Because he was under 21 at the time of the murders, he could not legally be given a life sentence with no minimum term. Abedi’s sentence is the longest determinate prison term ever handed down by a court in British legal history, according to BBC home affairs correspondent Danny Shaw.

“This is the end of one chapter for those affected by this terrible atrocity,” said Victoria Higgins, a lawyer for Slater and Gordon acting on behalf of 12 of the victims. “The families have waited a long time to see this man brought to justice and facing a life sentence for his crimes.” She added that “the next phase is about to begin” with a public inquiry into the attack due to start later this year.