At least four people have been confirmed dead after a bus rolled at the Nithi Bridge black spot along the Meru-Nairobi highway on Sunday noon.
County rescue services manager Alex Mugambi said several injured passengers have been rushed to various hospitals.
The bus which was coming from the Maua area in Meru county had 39 passengers onboard when it allegedly developed break failure.
Earlier on Tharaka Nithi county police commander Zacchaeus Ngeno confirmed the accident saying several passengers were feared dead and scores injured.
Ngeno then said the cause of the accident remained unknown as officers embarked on a probe into the fatal accident.
"We are still conducting a probe to establish the number of fatalities but we are certain that we had some fatalities," Ngeno said.
The county police boss urged drivers to be more vigilant and ensure their cars are in good shape to avoid accidents.
