One person died while three were seriously wounded when a parked truck rolled into Ortum market along Kitale–Lodwar highway on Friday evening.
The driver had stopped at the market to buy sugar while transporting goods from Kapenguria to Lodwar.
The vehicle hit a Nissan before ramming into shops and other structures.
Survivor Moses Kodeny, a Turkwel ward administrator who was in the Nissan, said it was hit as they alighted.
"We had tried to open the doors but could not. In the process of getting out through the window, the vehicle was hit," he said.
West Pokot Police Commander Mathew Kuto said police launched an investigation.
Several accidents have taken place in the area, the last case being that of a vegetable seller who was hit along the road.
To curb the incidents, Mr Kodeny asked the government to erect bumps in order to prevent motorists from speeding.
While noting that the road is steep, traders at the market asked the government to redesign it.
However, opinion leader Noel Long’onyiro noted the risk in erecting structures along the road.
One Samson Rotich said, “We have lost many people at this place so we need action to be taken."
Those injured were taken to Ortum Mission Hospital and the body to Kapenguria County Hospital mortuary.