The wreckage of a car involved on an accident with a trailer at Soysambu along the Nakuru- Nairobi highway. [Kipsang Joseph, Standard]

A medical-camp trip over the weekend turned tragic after four medics died following a grisly road accident along the Nairobi-Nakuru highway.

During the accident near Fly Over trading centre, the four died on the spot while scores of others were injured and rushed to hospital in serious condition.

The accident occurred after a lorry heading to Nairobi from Naivasha veered off its lane and hit the van that was carrying the medics.

The group was heading to Engineer town in Kinangop for a medical camp when the accident occurred, forcing the organizers to cancel the event.

A witness Paul Wangai said that the lorry driver was to blame for the accident, which paralysed traffic flow on the busy highway.

He said the medics were about to leave the highway and join the Magumu-Njabini road when the lorry that was speeding hit their van.

"The driver of the lorry was in high speed when he left his lane and ended up crashing on the medics van killing the four on the spot," he said.

Nyandarua South OCPD Francis Mwangi confirmed the accident noting that the injured were rushed to Kijabe Mission Hospital.

"We had an accident on Sunday where a lorry lost control and hit a van carrying 15 medics, killing four on the spot, and the bodies taken to Naivasha hospital mortuary," he said.

Meanwhile, a middle-aged man was crushed to death by a boulder while working in a quarry in Mai Mahiu, Naivasha.

The middle-aged man was pronounced dead on arrival at a local health centre in the town as operations in the quarry were suspended.

This is the second case in a month to be reported in the quarry located a few kilometres from Mai Mahiu town, with increased human activity blamed for the accident.

Naivasha OCPD Samuel Waweru confirmed the incident adding that the body had since been collected and taken to the local mortuary.

"The investigating officers have opened an inquiry file following the accident, and we have encouraged those quarry workers to observe safety measures in the future," he said.