A Japanese court on Thursday sentenced a 45-year-old man to death for setting fire to the renowned Kyoto Animation studio in 2019, which left 36 people dead in the country’s worst mass killing in almost 20 years, according to public broadcaster NHK, Paralel.Az reports.

The defendant, Shinji Aoba, was charged with murder and arson after telling police his work had been plagiarized and that he used gasoline to set fire to the studio. He was found guilty by the Kyoto District Court on Thursday.

Dozens of people were inside the three-story building at the time of the blaze, which spread so rapidly that many did not have time to escape, police said at the time. All those who died were employees, with at least 32 others injured.

In his ruling, the court’s presiding Judge Keisuke Masuda called Aoba’s crime “truly atrocious and inhumane.” The victims’ deaths were “too serious and tragic,” Masuda said, describing how flames and smoke engulfed the studio.

“The horror and pain of the victims who died in Studio 1, which turned into a hell in an instant, or who died afterward, is beyond description,” the judge said.

In a 2019 news conference, police said Aoba had unspecified mental health issues.

He pleaded not guilty at the trial, which began last September, with his defense lawyers arguing he had a mental disorder and could not be held criminally responsible.

Prosecutors however called for the death penalty, arguing Aoba was fully competent.

On Thursday, the judge ruled that Aoba could determine right and wrong at the time of the incident, according to NHK. His capacity for responsibility was “determined to have been neither insane nor mentally incompetent at the time of the crime,” NHK reported.