A party to a conflict may declare, as undefended, inhabited localities which are near or in areas where land forces are in contact when the localities are open for occupation by an adverse party. Bombardment in such a locality would be unlawful, if the following conditions were met and maintained: (1) no armed forces or other combatants present, (2) no mobile weapons or mobile military equipment present, (2) no hostile use of fixed military establishments or installations, (4) no acts of warfare by the authorities or the population, and (5) no activities in support of military operations.