It is unlawful for any person to give or make, or cause to be given or made, an alarm of fire without probable cause, or to neglect or refuse to obey any reasonable order of the Chief at a fire. To interfere shall include the following of the fire truck when its siren and emergency lights are in operation, closer than 500 feet, by persons not on official city business.
(’77 Code, § 203.12) Penalty, see § 10.99