Three survivors who talked to the Nation said the journey to western Kenya was jinxed from the word go.
While being treated at Fort Ternan Hospital, Mr Joseph Oponyo said the bus left the terminus at midnight.
The vehicle had hardly left the city when the driver was instructed to go make a U-turn and go for more passengers being transferred from another bus.
"The bus was overloaded. Some passengers sat on crates," Mr Oponyo said.
A row then ensued between passengers and the four conductors.
"They were rude, telling us to buy cars if we were not satisfied with their service," said the father of five who was heading to his Vihiga rural home.
He added that the bus sped and kept swerving. Passengers' pleas went unheeded.
"When we got to Tunnel, the bus swerved. We screamed as it began rolling and then there was silence. I don't know what happened next because I passed out," Mr Oponyo said.
He complained of pain and numbness.
VALLEY OF DEATH
A woman who spoke with difficulty and identified herself as Rosemary "Waaru" (unclear), was going for the burial of her father with her husband and two children.
Lying at Fort Ternan Hospital, her unease was not from the excruciating pain only. She was deeply worried about the whereabouts of her kin.
She kept calling out the name of her husband (Waaru).
Ms Katry Olimo, too, didn't know where her three-month-old baby was.
According to Fort Ternan residents, the area has become a valley of death, with at least two accidents occurring every month.
Nearly 20 accidents have been reported at the scene in the last one year.
Ms Catherine Chepkoech told the Nation that hundreds of lives have been lost on the 15 kilometre stretch between Siret and Muhoroni.
"This stretch of the road is synonymous with accidents but I have never seen one as horrendous as this. It's a dark day. I don't understand why the government cannot rectify this," she said.
Kipkelion West MP Hillary Kosgey and his Belgut counterpart Nelson Koech blamed the Chinese contractor for handing the government an incomplete road.
"As we send messages of condolence to the bereaved families, we call on the Kenya National Highways Authority to redesign this road before things get worse," the two lawmakers said.
"The road is incomplete, has no signage or markings. It is dangerous. Our disaster response is also poor."
Mr Koech said accidents had made families living downhill move to safer areas.
They also called for Kipkelion and Fort Ternan hospitals to be equipped with accident emergency units.
Shells of thermos flasks, sufurias and other household items were spread across the accident scene.
A sombre mood engulfed Kericho County Referral Hospital where relatives and friends trooped in to identify bodies.
The mortuary was overwhelmed as it has a capacity of 16 bodies only.
The Kenya Red Cross set up a counselling desk at the mortuary and helped in the identification of the bodies.