At least two police officers were injured on Monday night when a lorry driver rammed a roadblock on Thika Road.
Kasarani police boss Peter Mwanzo said officials believe the lorry driver was driving under the influence of alcohol.
One of the police officers is nursing severe injuries in his head and leg.
Mr Mwanzo said the lorry driver was ferrying rice towards the city when the accident happened at around 11pm.
“The driver sped past the barricade and hit one of our trucks before skidding on the wet tarmac and losing control of the vehicle which then overturned and hit a rail guard,”explained Mr Mwanzo.
Three passengers in the lorry survived the crash as well as the lorry driver, Mr Mwanzo said.
Police had a hard time rescuing the occupants of the lorry after they got stuck in the vehicle. A team from the fire brigade intervened.