Police in Kirinyaga are holding a man on suspicion of beating his 17-year-old son to death for smoking bhang.
The suspect was interrogated at the Wang'uru Police Station after the June 5 attack that left residents in shock.
The boy had lived with neighbours in the Kutus Mjini slums after his parents separated.
"The suspect and his wife were living in the same house together with their son who had dropped out of school. But the mother fled her matrimonial home, leaving her son with the father,” James Mwangangi, who knows the family, said.
“Later, (he) left moved to neighbouring homestead, where he lived as he did menial jobs for survival."
Last week, the son went to visit his father and found him alone in the house.
As they chatted, Macharia allegedly whipped out a roll of bhang, lit it and started smoking.
This was said to have angered his father, who took a stick and repeatedly struck the boy on the head and the teenager fell to the floor.
The boy raised the alarm, attracting neighbours, who rescued him.
The neighbours called the teenager’s mother, who rushed him to Kerugoya Referral Hospital, where he was admitted unconscious.
He succumbed to his injuries three days later.
Kirinyaga East police boss Daniel Kitavi said this was an isolated incident and was being treated as a murder.
"We have arrested the suspect, who is a casual labourer, and soon he shall face a murder charge," Mr Kitavi said.
He said the suspect should not have attacked his son for abusing drugs.
He advised parents to take their children who are drug addicts to rehabilitation centres instead of assaulting them.
"Parents should be responsible enough. They should help their children to reform instead of subjecting them to corporal punishment, which can lead to death," he said.