Arson investigators with metal detectors could be seen outside going through the rubble outside the site of the law office of House Speaker Joe Shekarachi. Sources close to the investigation say the last person to leave the office Tuesday night was at 8:30, an hour before the fire broke out. An unconfirmed eye witness claims to have heard an explosion at 9:30pm, followed by a vehicle speeding away from the scene. Several motives have emerged including frustrated cannabis growers who are upset with the Speakers actions on cannabis licenses. This story is developing.