Every person, except the owner or lessee of the premises, his family and nonrioting guests, and public officers and persons assisting them, who remains at the place of any riot or unlawful assembly after having been lawfully warned to disperse, shall be guilty of a Class 3 misdemeanor.

Code 1950, § 18.1-254.4; 1968, c. 460; 1971, Ex. Sess., c. 251; 1975, cc. 14, 15.