AUBURN — The state Fire Marshal’s Office has ruled that an early morning fire at the site of a proposed slaughterhouse in central Maine was arson.

The Auburn City Council voted 4-2 Monday night to allow slaughterhouse operations in the city’s agriculture zone, clearing the way for a slaughterhouse proposed on Trapp Road. In the weeks leading up to the vote, scores of signatures were collected on a petition opposing the zoning change.

Hours after the vote, a fire was reported early this morning at a building that would house the slaughterhouse. Sgt. Joel Davis of the Fire Marshal’s Office told the Sun Journal of Lewiston he isn’t releasing the cause of the fire, but said people are being interviewed as part of the investigation.