(a) The county fire marshal's office shall investigate the cause, origin and circumstances of every fire occurring in the town which is of a suspicious nature or which involves loss of life or injury to persons, or when notified by any fire department of a fire protection district or when circumstances warrant. Such investigation shall begin immediately upon the occurrence of such a fire and, if it appears that such fire is of suspicious origin, the county fire marshal shall be immediately notified and coordinate investigation activities with the fire department having jurisdiction. Any information obtained pursuant to any such investigation shall be confidential as authorized by law.

(b) The sheriff's department or town police department, upon request of the fire marshal or his authorized representatives, may render such assistance as necessary in the investigation of any fire determined to be of suspicious origin.