A 76-year-old former top bureaucrat of the farm ministry arrested for the murder of his son suggested during police questioning that his son's social withdrawal and violent behavior were the motive behind the act, investigative sources said Sunday.

The police arrested Hideaki Kumazawa, also a former Japanese ambassador to the Czech Republic, on Saturday for stabbing his 44-year-old son Eiichiro to death at their home.

Social withdrawal was recently highlighted again as a serious social problem in Japan by a mass stabbing Tuesday in Kawasaki near Tokyo by an assailant who is said to have hardly left his home where he was living with his uncle and aunt in their 80s.


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Former top farm bureaucrat arrested over alleged murder of son


The investigative sources quoted Kumazawa as saying his son "tended to be withdrawn from social life and showed violent behavior" toward him and his wife.

The former bureaucrat also suggested to the police he became worried about the possibility of his son acting impulsively and harming people, the sources said.

According to a government survey released in March, there are an estimated 613,000 people aged between 40 and 64 who are socially withdrawn or isolated, with job-related problems being the biggest reason for starting to avoid contact with other people.

The survey also showed 540,000 people aged between 15 and 39 have become socially withdrawn, but the government sees the problem as potentially more serious for older generations facing financial difficulties as their parents get old.

Kumazawa joined the predecessor of the Ministry of Agriculture, Farm, Forestry and Fisheries in 1967, and became the ministry's top bureaucrat in 2001.

He stepped down the following year amid criticism of the ministry's handling of a mad cow disease outbreak. He served as Japan's ambassador