Japanese man who killed his son with kitchen knife ‘after he was violent towards mother’ jailed

Former government official Hideaki Kumazawa stabbed 44-year-old Eiichiro more than 30 times

Hideaki Kumazawa leaves a police station in Tokyo earlier this year (AP)

A former Japanese government official has been sentenced to six years in prison after killing his son with a kitchen knife.

Hideaki Kumazawa stabbed 44-year-old Eiichiro​ in the neck and chest more than 30 times at their home in Tokyo before immediately calling the police and admitting to the crime.

The 76-year-old, a former vice minister of agriculture, forestry and fisheries, pleaded guilty during a trial at Tokyo District Court.

His son suffered from a development disorder and was routinely violent towards his mother, the court heard.

Eiichiro, who died from massive blood loss, was removed from his parents and lived alone in an apartment before returning home a week prior to his death in June.

He subsequently became violent again, the court ruling said, and threatened to kill his father.

Kumazawa’s lawyers claimed their client had acted in self-defence and was fearful his son might harm others.

Days earlier, another reclusive man – known in Japan as hikikomori – stabbed to death two people and wounded 17 others, many of whom were schoolchildren, at a bus stop outside Tokyo.

But judge Tomoyuki Nakayama dismissed the lawyers’ appeal for a suspended sentence, arguing that the number of stab wounds inflicted by Kumazawa indicated the killing was not purely self-defence.

Prosecutors pushed for an eight-year prison term but the court settled upon six, taking into consideration Eiichiro’s violent behaviour and threat to kill his father.

Speaking during the closing court session, Kumazawa said: “It is my duty to pay for the crime and pray for my son so he can pave a peaceful time in his afterlife.”

According to a government survey in March, there are an estimated 610,000 hikikomori between the ages of 40 to 64 in Japan.

The Japanese Ministry of Health, Labour, and Welfare defines hikikomori as individuals who isolate themselves at home, away from society and work, for a period exceeding six months.

Many are looked after by their parents and receive little support from social services.