Interior CS Fred Matiang'i has ordered the arrest of an officer who gunned down his colleague in Kiambu on Thursday.
Chief inspector Duncan Maina of DCI headquarters fatally shot Evanson Kipngetich Busienei as the latter was walking back to Thindigua police post.
A police report said that Maina alleged Busienei, in the company of another man, stopped him and demanded he be given the vehicle he was driving.
He said that the vehicle bearing reg no KAU 429U belonged to the DCI.
"The DCI officer has since been disarmed," read the statement.
Speaking in Nairobi on Friday, Matiang'i said he had talked with Inspector General Joseph Boinnet over the issue.
"Something is not adding up," he said.