The coroner’s physician may order forthwith the cremation of the remains of any person appearing to have come to death under any of the circumstances set forth in § 841-3 if, in the coroner’s physician’s opinion, the remains constitute an immediate menace to the public health. The cremation shall be supervised by the coroner and shall take place only after a reasonable amount of investigation has taken place in an effort to establish the identity of the remains and the cause of death. Such cremation shall take place after a burial-transit permit authorizing cremation has been secured from the local agent of the department of health.