A prisoner was killed and eight others sustained seriously injuries on Tuesday in an accident along the Runyenjes-Chuka road in Embu County.
The Embu Prison vehicle was ferrying inmates to Meru when it overturned at Kathageri village near the Thuci River.
Seven prison warders were also hurt in the morning incident.
The victims sustained hand and leg injuries and were rushed to Chuka hospital for treatment.
The body was taken to the mortuary in the same facility.
Embu County Police Commander Mr Daniel Rukanga confirmed the incident.
"It is true one inmate succumbed to injuries on the spot and several others injured. Warders who had accompanied the prisoners were also injured," said Mr Rukanga.
According to eyewitnesses, the driver lost control of the vehicle and crashed into an embankment, killing one of the inmates on the spot.
Some of inmates were thrown out of the vehicle and landed on the rocks.
"We saw the GK van swerve and veer off the road before it ploughed into the embankment," said Mr Muturi Njagi.
Another witness said he was at home when he heard a loud bang.
"I ran to the scene and I was shocked to find one person dead and several others writhing in pain," he said.
Some of the inmates were trapped in the mangled vehicle and residents and the police used axes to cut the metal to free them.
The accident caused a major traffic snarl-up as rescuers blocked the road.