(a) The Bureau of Fire Prevention shall investigate the cause, origin and circumstance of every fire occurring in the City which is of suspicious nature or which involves loss of life or injury to persons or by which property has been destroyed or substantially damaged. Such investigation shall be begun immediately upon the occurrence of such a fire by the Chief Inspector, and if it appears that such fire is of suspicious origin, the Chief Inspector shall be immediately notified of the facts; he shall immediately take charge of the physical evidence, 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 in the prosecution of the case.
(b) The City Attorney and the Chief of Police, at the direction of the City Manager and upon request of the Chief Inspector, shall assist in the investigation of any fire, which, in their opinion, is of suspicious origin.
(1977 Code Sec. 27.17)