In June 2008, Kato, who was 26 at the time, attacked Tokyo's busy Akihabara shopping district by ramming a truck into a crowd of pedestrians and then stabbing passersby. As a result, seven people were killed and 10 were injured.
After the detention, the criminal said that he had specifically come to Tokyo from Shizuoka Prefecture to kill someone, as he had lost all interest in life.
According to the indictment, Kato did not suffer from mental disorders and, therefore, was conscious of his actions. On the basis of the evidence provided, as well as the results of the investigation, the court sentences him to capital punishment.
The Supreme Court finalized Kato's death sentence in 2015, rejecting his appeals and saying that the seriousness of the crime made the verdict unequivocal.
The criminal was executed on Tuesday morning at the Tokyo detention center.
In the judicial practice of Japan, the death penalty is usually applied in cases of the murder of multiple people. Generally, the capital punishment in Japan is carried out through hanging a few years after a court considers the verdict. International human rights organizations have been urging Japan to give up capital punishment. A convicted person may wait for the execution of the sentence for years until the morning they are told the execution is about to happen.