As used in this chapter, the following terms shall have the meanings indicated:
A riot or unlawful assembly characterized by the use of actual force or violence or any threat to use force if accompanied by immediate power to execute by three or more persons acting together without authority of law.
Any natural disaster or man-made calamity, including flood, conflagration, cyclone, tornado, earthquake or explosion, within the corporate limits of Pocomoke 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.
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 Pocomoke City, excepting persons officially designated to duty with reference to said civil emergency.