“I’m glad they’re dead,” Axel Rudakubana, who is accused of the murders of three girls during a dance class at Southport in Britain last July.

The 18-year-old killed Bebe King, six, Elsie Dot Stancombe, seven, and Alice da Silva Aguiar, nine, and tried to kill ten other people during the Taylor Swift-themed event.

Opening the trial today, prosecutors said Rudakubana carried out a “premeditated knife attack against several victims, mostly young girls, with the intent to kill them” and inflicted injuries that “are difficult to explain as anything other than sadistic in nature.” Liverpool Magistrates’ Court was also told that Rudakubana said “I’m glad they are dead” as he was detained after killing the three girls.

The hearing in the case continued today despite the perpetrator being taken to hospital in the early hours of the morning, according to the Daily Mail. Although he needed “medical attention”, his condition was not deemed serious enough to postpone the hearing.

A parent of a girl injured in the attack asked the judge to show no leniency to Rudakubana and to “take him to jail.”

Rudakubana, who was born in Cardiff to Christian parents who migrated from Rwanda, had been caught with knives on him ten times and police had visited his home five times over reports of “annoying behaviour”.

As it became known, Rudakubana had been referred three times to the government’s counter-extremism program Prevent because of an obsessive interest in extreme violence and bloody clashes. At the age of 13, he was forced to leave his previous school after a series of incidents, including having a knife on him and attacking pupils with a hockey stick.

Before he went in and attacked children in dance class with a kitchen knife, he planned an attack at his old school a week earlier on July 22. The attack was thwarted when his father stopped him from getting into a taxi outside the family home.

Rudakubana, pleaded guilty Monday to the charges against him.