A civil emergency is hereby defined as:
(1) A riot or unlawful assembly characterized by the use of force or violence disturbing the public peace, or any threat to use such force or violence, if accompanied by immediate power of execution, by two (2) or more persons acting together without authority of law; or
(2) Any natural disaster or man-made calamity, including flood, conflagration, windstorm, tornado, earthquake or explosion within the corporate limits of the city resulting in the death or injury of persons or the destruction of property to such an extent that extraordinary measures must be taken to protect the public health, safety and welfare.
Curfew is hereby defined as a prohibition against any person or persons walking, running, loitering, standing or motoring upon any alley, street, highway, public property or vacant premises within the corporate limits of the city excepting persons officially designated to duty with reference to said civil emergency.
(Ord. No. 3514, § 1, 9-8-70)