The accident occurred at Kamureito trading centre in Sotik Sub-County.
Three people have died, while nine others have been injured after a matatu they were travelling in veered off the road and rolled on the Bomet-Kaplong highway.
The driver of the vehicle and his conductor died on the spot. The accident occurred at Kamureito trading centre in Sotik Sub-County on Sunday.
One other passenger, who sustained multiple injuries, died while undergoing treatment.
"Two people were pronounced dead on arrival at Kaplong Mission Hospital, while the other one died while undergoing treatment, " said Bomet County Police Commander Naomi Ichami.
Ms Ichami said vehicle was travelling from Kericho to Bomet when a tyre burst, before it veered off the road and rolled several times.
Bodies of the victims were moved to Kaplong Mission Hospital mortuary.