Officials with California State Parks says the burning down of the historic Bidwell Mansion was arson..... Aaron Wright is the District Chief for California State Parks. He says they have opened up an arson investigation into the loss of the 156 year-old Bidwell Mansion. Last Wednesday the centerpiece of downtown Chico burst into flames. Witnesses say they saw someone leaving the scene. Wright says all evidence collected from the site leads them to believe the mansion was intentionally set on fire. He says they are following all leads collected in the immediate aftermath of the fire. The Bidwell Mansion Fund has been set up by the North Valley Community Foundation to help in efforts to rebuild, memorialize and commemorate the Bidwell Mansion.