Three people died on Tuesday when the personal car they were travelling in was crushed between two trailers near Maanzoni Lodge along the Nairobi-Mombasa highway.
The victims, who died at the scene of the accident, were the drivers of the two trailers and a turnboy.
David Mwongela, the Machakos County Emergency Services director, said one of the trailer drivers lost control and veered to the opposite lane while heading to Nairobi.
He ended up hitting the other trailer and the personal car, a Toyota Probox.
"The driver of the Probox sustained serious injuries," said Mr Mwongela.
He said the Mavoko fire fighters were among the responders.
Athi-River Sub-county Police Commander Catherine Ringera said the survivor was taken to Machakos Level 5 Hospital and the bodies to its morgue.