A Tokyo court on Friday sentenced a 37-year-old man to 19 years in prison for stabbing three passengers in a random knife attack on a Tokyo commuter train in 2021.

Yusuke Tsushima, who had admitted to the charge of attempted murder of the three victims, "attacked passengers randomly one after another with a strong intent to kill," said the ruling handed down at Tokyo District Court.

"There was a high risk of threat to life and it was extremely vicious," the ruling said.

In the trial, prosecutors had demanded 20 years in prison for the defendant, while his defense team requested 15 years, arguing his intent to murder was insufficiently strong.

Rescue workers take out stretchers after passengers were stabbed on an Odakyu Electric Railway commuter train in Tokyo's Setagaya Ward on Aug. 6, 2021. (Kyodo)

According to the indictment, Tsushima seriously injured a then 20-year-old university student by stabbing her several times in the chest and back and also injured a woman in her 50s and a man in his 30s on an Odakyu Electric Railway train on Aug. 6, 2021.

He was also accused of shoplifting groceries and other items at several stores in Tokyo and neighboring Kawasaki before the stabbing incident, according to the indictment.

In trial proceedings, Tsushima, who was unemployed for several months prior to the incident, said he had long harbored a desire to commit random mass murder and fantasized about killing women he perceived as "successful" in life, such as those looking happy with their partners.

He also said he considered himself "unlucky" and "always had a sense of inferiority and a jealousy-like feeling, which could only be transformed into hatred" toward other people.

The knife rampage took place a few months before another man dressed in a Joker's costume stabbed a man and started a fire onboard a Tokyo train in October 2021.

In his first trial at the Tokyo District Court last month, prosecutors said the defendant, Kyota Hattori, conceived the attack on the Keio Line train after seeing media reports about the knife attack on the Odakyu commuter train.

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