A man was shot and killed by unknown gunmen in Kist area, Kiambu Township.
Witnesses said the incident happened on Thursday, August 1, along Kist-Degro Road.
The motive of the attack is yet to be known, police said.
Police said they arrived at the scene and found the lifeless body of an unknown man aged about 27 years lying beside a motorcycle.
The body had one gunshot wound in the chest while two spent 9mm cartridges and one live bullet were recovered about 100 meters from the body.
It was alleged by guards near the scene that the rider was being followed by two other motorcycle riders who fled the scene immediately after the shooting.
The body was moved to the City mortuary awaiting postmortem and identification.
Police termed the killing an execution.
Elsewhere, police are investigating the death of a man whose body was discovered in City Stadium area, Nairobi.
The man did not have identification documents when police arrived at the scene to pick up the body to the mortuary.
The victim had no visible injury nor was there a sign of struggle at the scene, police said.
The body was moved to the mortuary pending identification and autopsy.
Meanwhile, a police officer is nursing a head wound after he was stoned by a man he was stopping from exhuming a body in a village in Kaimosi area, Nandi County.
Two police officers had rushed to Kiborgok village to stop a man from exhuming the body of one Darling Rukabite when the incident happened on Wednesday afternoon, police said.
The team arrived at the scene and found the suspect in the process of exhuming the body and when he was cautioned not to continue, he picked two stones and hurled them at the officers hitting one of them in the head.
Angry residents landed on the suspect with stones and twigs before police stopped them.
The suspect and the officer were taken to Kapkangani Health Centre where they were treated and discharged in fair condition.
The suspect was expected in court on Friday, police said.
Police linked the planned exhumation to a land dispute, which they argued should be solved amicably.
Local officials have been asked to intervene and solve the matter.
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