A Githurai 45-bound bus was set ablaze by bodaboda riders along Thika Superhighway on Saturday afternoon.
The angry motorcyclists set the bus on fire after the bus hit a bodaboda operator near Roysambu and the driver ran away.
The injured motorcyclist was rushed to hospital but the passengers in the bus were unhurt.
The incident caused a major snarl-up on lane to Thika as some commuters stopped to watch the PSV bus go up in flames.
Thika-bound motorists were advised to use service lanes or alternative Zimmerman route.
Kasarani Division Traffic Officer (DTO) Charles Mwangangi urged road users not to take the law into their hands but use the prescribed measures. "Let's all learn to use the prescribed avenues to solve traffic occurrences and not take law into our own hands," said Mwangangi.