Kenyan police on the trail of one of the country's most wanted criminals shot dead a 17-year-old boy after mistaking him for their suspect, the boy's father said on Tuesday, in the latest accusation of wrongful killing to be levelled at the force.

Kenyan police face frequent allegations of brutality and extrajudicial killings from civilians and rights groups, but officers are rarely charged and almost never convicted.

The police service was not available immediately for comment on the accusation by the boy's father, Thomas Okong'o, who told Reuters his son, Arnold Mudanya, was shot dead as he left a shop in Nairobi's Eastlands area on Friday morning.

Okong'o said the police had mistaken his son for Shimoli Junior, described by local media as one of the country's most wanted men.

‘Police have killed my son due to mistaken identity. They should not take the law into their hands... they should have arrested him if he was a suspect,’ he said. Mudanya was working as a tout on public minibuses in the area before he was killed, his father said.

Local media quoted the police as saying they had shot dead a suspect identified as Shimoli Junior soon after Mudanya was killed. Police had accused Shimoli of attacking sports men and fans in a stadium in the area.

Okong'o said he had reported the killing at a police station and with the Independent policing oversight authority (IPOA). IPOA was not immediately available for comment.

State-funded IPOA was established by the government in 2011, after police were blamed for the deaths of dozens of protesters in violent following a disputed presidential election in 2007.

But it has only managed to secure a handful of convictions against accused policemen despite numerous complaints against the police from the public.