The Fire Prevention Bureau shall investigate the cause, origin and circumstances of every fire occurring in the City by which property has been destroyed or damaged and, so far as possible, determine whether the fire is the result of carelessness or design. Such investigations shall begin immediately upon the occurrence of such a fire by an assistant officer making such an investigation, and if the fire is of suspicious origin, the Fire Chief shall be immediately notified of the fact. He shall immediately take charge of the physical evidence, shall notify the proper authorities designated by law to pursue the investigation of such matters, and shall further cooperate with the authorities in the collection of evidence and in the prosecution of the case. Every fire shall be reported in writing to the Fire Prevention Bureau within two days after the occurrence of the same by the officer in whose jurisdiction such a fire has occurred. The report shall be in such form as prescribed by the Fire Chief and contain a statement of all facts relating to the cause, origin and circumstances of the fire, the extent of the damage thereof, the insurance upon property and such other information as may be required. (1965 Code §8-25)