Four people died after their bus plunged into a ditch at Kwa Solo in Makueni County on Friday.
Mbooni West OCPD Mathew Ngwio said several others sustained injuries and were taken to Tawa and Mbooni hospitals.
"The driver lost control and the vehicle plunged into a ditch," Mr Ngwio said, adding that they were coming from a burial ceremony.
The incident happened on the Kikima-Machakos road.
Two years ago, nine passengers died after their overloaded matatu fell into the same ditch.
Motorists and residents have been asking the government to put up guard rails at the spot to limit such incidents.