From the reports made to him, the state fire marshal shall keep a record of fire losses occurring in this state and of facts concerning them. He shall make the compilations, investigations and statistical summaries he deems proper, all of which shall be kept as permanent records in his office. All records shall be public, except that the state fire marshal may, in his discretion, withhold from the public, statements and testimony taken in an investigation or examination, correspondence relating to an investigation or examination, confidential reports of private persons and agents, and reports of investigations of fire losses, but any records withheld as herein provided shall be available to the prosecutor of the county in which the fire loss occurred.