A Japanese man was sentenced to death yesterday for the stabbing murder of 19 disabled people at a care home, in one of the country’s worst mass killings.

Satoshi Uematsu never disputed his involvement in the grisly rampage but his lawyers entered a plea of not guilty, arguing the 30-year-old was suffering a “mental disorder” linked to his use of marijuana.

The court ruled that the former employee of the facility deserved no leniency over the 2016 attack, which shocked the country.

“The lives of 19 people were taken away. This is profoundly grave,” chief judge Kiyoshi Aonuma told the court. Uematsu planned the murders and had “an extreme intention to kill”, he added.

Prosecutors had sought the death penalty—which in Japan is carried out by hanging—and argued that the defendant was capable of taking responsibility for the violence at the Tsukui Yamayuri-en centre, just outside Tokyo. Uematsu was impassive as the verdict was announced, looking straight ahead at the judge as he was sentenced.

He wore a black suit with his hair in a long ponytail down to his waist, and was flanked by six uniformed court officers wearing surgical masks. Uematsu, who faced six charges including murder, reportedly said before the trial that he would not appeal any verdict, though he argued he did not deserve the death penalty.