Related Rule
Russian Federation
Practice Relating to Rule 6. Civilians’ Loss of Protection from Attack
Section C. Situations of doubt as to the character of a person
The Russian Federation’s Regulations on the Application of IHL (2001) states: “In case of doubt whether a person is a civilian, that person shall be considered a civilian.” 
Russian Federation, Regulations on the Application of International Humanitarian Law by the Armed Forces of the Russian Federation, Ministry of Defence of the Russian Federation, Moscow, 8 August 2001, § 1.