Criminal Intelligence Unit officer Muhammad Khamisi was shot dead by hooded gunmen near Fort Jesus in Mombasa on Wednesday.
Khamisi was accosted and killed outside a square in Mombasa Old Town at about 9pm, said regional deputy county police boss James Kithuka.
Speaking at the scene on Wednesday, Kithuka said he was rushed to Mombasa hospital where he was pronounced dead upon arrival.
He said the attackers stole the pistol of the officer who was attached to Kenya Ports Authority.
Kithuka said a manhunt was launched for the suspects believed to have killed several in the county.
Khamisi will be buried today at Kikowani Muslim Cemetery.