The death toll from the Mai Mahiu rose after a patient undergoing treatment died at Naivasha sub-county hospital.
The accident occurred after a mini-bus ferrying mourners from Kisii to Naivasha was involved in an accident with a lorry transporting sand along the Mai Mahiu-Narok road.
Seven of the victims died on the spot, the eighth on arrival at Mai Mahiu health centre and the ninth died at Naivasha Hospital.
Six of the nine victims were identified as members of St Ann Catholic parish in Kongoni, Naivasha.
According to the superintendent in charge of the hospital Dr Angeline Ithondeka, a total of 16 patients were brought to the facility following the Saturday morning accident.
Some 11 had been treated and discharged while five were in a critical condition.
“One of the patients however passed on while undergoing treatment and we shall transfer some to PGH in Nakuru for specialised treatment,” she said.
Hospital chairman Gatheru Mwangi said they were well equipped to handle the casualties.
Speaking on phone, Naivasha OCPD Samuel Waweru said four sand loaders in the ill-fated lorry were also seriously injured.