President Uhuru Kenyatta has sent a condolence message to the families of Kericho accident victims.
In his message, the President offered his remorse to the families and wished those in hospital quick recovery.
The head of state also called on drivers to exercise caution while driving to avoid such accidents.
Kenyatta promised investigations into the cause of the Wednesday morning accident.
"My heartfelt condolences to the families of fellow Kenyans who lost their lives in a tragic road accident at Fort Ternan in Kericho County this morning and wish those in hospital quick recovery. As authorities investigate the cause of the accident with a view of taking action, I would like to remind drivers to always exercise caution to avoid such catastrophic incident," President Kenyatta said.
The 4 am accident took place at the tunnel in Fort Tenan, Kericho and the bus, heading from Nairobi to Kisumu, is said to have collided with a truck before losing control.
The death toll has since risen to 50 from the initial 42 that was reported immediately after the crash.
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