Twelve students of Moi University sustained slight injuries when their bus was involved in an accident along the Nairobi-Nakuru highway at Kimende town in Lari subcounty.
Lari subcounty deputy police commander Francis Njomo said the students were rushed to Orthodox Hospital in Kimende town.
Njomo confirmed that the bus had 50 students.
The bus was ferrying third-year and fourth-year Kiswahili students to Mombasa.
"The driver of the bus lost control in unclear circumstances and the bus landed in a ditch," Njomo said,
He said traffic police have launched investigations to establish what happened before the accident.
"We are investigating to establish how the driver lost control and the bus got off the road," he said.
However, an eye witness John Kimani said the bus driver was trying to escape another car that was being driven carelessly.
Kimani has asked motorists to drive carefully, especially at Kimende, Uplands, Magina, Kinale and the environs since the area is covered by mist in the morning and evening.
"No one needs to over-speed, the weather is very chilly. The roads are slippery and you cannot see the distance one is required to see when one is driving" Kimani added.
Njomo said the wreckage of the university bus was towed to the Lari police station as investigations continue.
The accident comes barely two weeks after 11 Kenyatta University students lost their lives in a grisly road accident at Maungu, Voi, Taita Taveta county, along the Mombasa-Nairobi highway.
The 11 were among a group of 58 others heading to Mombasa for an academic trip before their school bus collided with a trailer.