According to witnesses, Senior Private Joseph Mwangi, 30, was walking home around 8 p.m. when he was approached by three thugs riding on motorcycles.
The gang demanded his backpack, which sparked a fight that resulted in the shooting.
Private Mwangi was then shot in the back by one of his assailants, who then fled with the bag.
Guards from a nearby residence rushed to the scene and rushed the officer to the hospital, where he was pronounced dead on arrival.