The state fire marshal shall, when in his opinion the proceedings under N.H. Rev. Stat. § 153:18 are necessary, take or cause to be taken the testimony on oath of all persons supposed to be cognizant of any facts or to have means of knowledge in relation to the matters concerning which such examination is made, and cause the same to be reduced to writing. If he shall be of the opinion that there is sufficient evidence to charge any person with the crime of arson or incendiarism he shall furnish to the appropriate law enforcement agency all such evidence together with the names of witnesses and all information obtained by him, including a copy of all pertinent and material testimony in the case.