Five people among them a primary school pupil died on the spot in separate road accidents on the Nairobi-Mombasa highway.
Police said three of the victims died at Manyani, one at Caltex, while the fifth died in Maungu Township on the busy highway.
In the Manyani accident, Voi Traffic Base Commander Michael Mureithi said a car heading to Nairobi entered the wrong lane and in the process collided with an oncoming truck, killing three passengers on the spot.
In the second accident, a primary school pupil died on the spot after he was knocked down by a truck while crossing the highway in Maungu Township.
In the third incident, an old man who was crossing the highway at Caltex junction was killed by a speeding truck.
Mr Muriithi warned motorists against flouting traffic rules.
The scenes of the accidents are regarded as major blackspots in the country.
The bodies were moved to Voi referral hospital mortuary.
The accidents bring to seven the number of people who have died as a result of road accidents in the region.
Two days ago, two people died while 28 others sustained serious injuries at Josa Hill on the Mwatate-Wundanyi road.
According to police, the driver of the bus lost control of the vehicle while descending the steep hill before overturning killing one and seriously injuring 28 others.
The victims, who suffered multiple injuries, are still recuperating at Voi county referral hospital.
County police commander Fred Ochieng advised passengers to report drivers who are speeding.