A brief video clip showing a civilian wrestling and exchanging punches with a police officer at a police station in Nakuru has stirred debate on the internet.
In the 10-second clip, the officer slaps the civilian, who in turn punches him before a fight ensues.
Other police officers and civilians at the station quickly intervene and end the scuffle.
The Nation has independently established that the fighting occurred at the crime reporting desk at the Nakuru Central Police Station in Nakuru city.
"The man and others had arrived to report a crime when the incident happened," a source told the Nation.
Nakuru County Police Commander Peter Mwanzo confirmed the incident.
"The incident happened at the Nakuru Central Police Station but it is under investigation. I have asked the Officer Commanding Police Division (OCPD) to share details of the incident so that l can understand what exactly happened," Mr Mwanzo told the Nation.
He said the civilian was arrested and was in custody as investigations continue.
The clip begins with the civilian being slapped in the face by the visibly angry police officer before the two engage in a fistfight.
The short man is shown trying to wrestle the unarmed officer to the ground.
Witnesses, including other police officers, appeared shocked at the incident.
The clip was posted on Facebook by a user who calls himself Abdulahi Adan on Thursday morning.
During the confrontation, the police officer could be heard warning the civilian that he would not leave the police station.
"Hutoki ... hutoki, I assure you” (You will not leave this place, I assure you, you will not), the officer is heard telling the man.
But the man responds: “What have I done to warrant a slap. I haven't done anything.”
Some voices were heard warning the attacker that it was suicidal to fight a policeman at a police station.
It is not clear what happened to the civilian afterward.
Social media users were shocked at the incident, with some sympathetic to the civilian as others making jokes about the incident.
"It was not good for the police officer to slap him. He started the fight because he provoked him. I only hope he managed to leave the police station safely,” wrote John Abdi.
A Facebook user named El Patron Raju said: "The police officer was the first to assault the man. The man should just be escorted home."