Police have arrested a man in connection with the murder of his six-year-old nephew, whose body was found dumped inside a culvert along the Runyenjes-Embu road in Embu County last week.

The man, whose name we have withheld for legal reasons, was arrested in Dandora, Nairobi, on Sunday, as police seek to establish who killed six-year-old Brian Munene.

Officers from Ena police station had put out an alert to their colleagues, as they sought to bring Brian’s uncle in for questioning on account of being the last person to be seen with the six-year-old boy alive.

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Brian was an orphan and lived with another uncle, Moses Fundi, in Ivari village in Runyenjes, Embu County.

A neighbour in Ivari told police that he saw Brian and a visiting uncle walk out of the village together that evening.

The uncle who has been arrested lives in Dandora but also has a home he frequently visits in Ivari village.

The Directorate of Criminal Investigations (DCI) has since taken over the probe.

At around 10pm on August 21, Moses Fundi filed a missing person report at Runyenjes police station.

Fundi does casual work in Runyenjes. He told officers that when he returned home from work, Brian was not home and was not in any of the neighbours’ homes.

Fundi, who is a casual labourer, told investigators that he had left the son home alone and did not find him when he came back in the evening.

Villagers in Ivari initiated a search for Brian that same night.

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At 6am the following morning, as police were preparing to circulate information about Brian to colleagues across the country, the villagers found the six-year-old’s body in a culvert in the Gikuuri area, and alerted police.

Officers from Ena police station visited and documented the scene.

Brian’s body was found with injuries. Brian’s body had mutilated genitals, indicating possible sexual assault.

There was swelling on his head, a cut on his left thigh and bruises on the neck, indicating that Brian was possibly strangled.

On his chest, some political words were engraved. His body was moved to Tenri Mortuary, pending postmortem.

The motive of the murder is still unknown.

Police arrested the uncle under the “last seen with” doctrine.

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Under the legal principle, an individual can be prosecuted for murder if he or she is proven to be the last person seen with the victim alive but cannot prove that they parted ways before the death occurred.

However, other evidence is usually required in those instances.

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kamaina@ke.nationmedia.com