A mother, her three children and a friend were killed on Tuesday after fire gutted a house in Geta town, Kipipiri.
Kipipiri police boss Charles Rotich said the fire broke out at 3am.
The woman was only identified as Murugi.
Neighbours were woken up by screams, but were unable to save the victims because the fire spread through the wooden house too fast.
Police are yet to establish the cause of the fire, but a jiko or kerosene lamp is suspected to behind it.
The bodies were taken to JM Memorial Hospital mortuary as investigations begin.
Geta MCA John Githinji said, “For now we cannot say it was something plotted, but police are investigating.”
He said one girl who was heard screaming could have died of suffocation as the neigbours tried to put out the fire.
Geta area is windy, making it difficult to put out a fire.