Related Rule
Kenya
Practice Relating to Rule 19. Control during the Execution of Attacks
Kenya’s LOAC Manual (1997) provides: “The attack shall be deviated or cancelled if the objective or target appears not to be military.” 
Kenya, Law of Armed Conflict, Military Basic Course (ORS), 4 Précis, The School of Military Police, 1997, Précis No. 4, p. 9.
The manual further specifies that: “If the resulting loss or damage of a military operation would be excessive in relation to the concrete and direct military advantage excepted, the operation must be cancelled or suspended.” 
Kenya, Law of Armed Conflict, Military Basic Course (ORS), 4 Précis, The School of Military Police, 1997, Précis No. 4, p. 1.