Takahiro Shiraishi, 30, has been sentenced to death after killing and dismembering nine people.

The Tachikawa branch of the Tokyo District Court in Japan found Shiraishi guilty of killing the victims and storing their bodies in an apartment in Zama, per a report from the Associated Press. Shiraishi, who has been widely referred to in global headlines as the "Twitter killer," was arrested in 2017 after authorities found the bodies of eight women and one male inside cold-storage cases in his Zama apartment.

According to investigators, Shiraishi had initially made contact with his eventual victims on Twitter by offering to help them with "suicidal wishes" and inviting them to his apartment. In some instances, investigators said, Shiraishi had told his victims he would also take his own life. Shiraishi killed the women, some of whom were teenagers, after raping them. He also killed the boyfriend of one of the victims. Shiraishi's victims, killed between August and October of 2017, ranged in age from 15 to 26.

During court proceedings, Shiraishi ultimately contradicted the argument from his attorneys that he had helped the victims with their suicidal wishes. Instead, Shiraishi later admitted, he had killed the victims without their consent. After pleading guilty, Shiraishi told the court he would not appeal his sentence.

"It was easier for me to convince people with worries and other issues and manipulate them to my way of thinking," Shiraishi, whose murders inspired new Twitter site policies and an expansion in Japan of mental health support services, said during the trial, per NPR.