The Department shall examine, or cause examination to be made, into the origin and circumstances of all fires occurring in this Commonwealth, which may be brought to its attention by official report, or otherwise, and for that purpose shall have authority to call for and demand of the chief or other head officer of the fire department, and the chief or other head officer of the police department, of any city or town, and the sheriff of any county, for any information or assistance it may require in making or furthering such examination. The Department shall appoint a chief arson investigator and assistant arson investigators, who shall have the same police powers as a sheriff in the investigation and prosecution of all offenses involving fires, fire bombings, bombings, attempts, threats to commit such offense, false alarms relating to any such offense, possession and manufacture of explosive devices, substances and firebombs.