Federal officials are joining the investigation into a church fire in Millinocket. They say it was intentionally set in two places inside the Church of the Nazarene. According to Sgt. Scott Richards of the state fire marshal's office, the pastor discovered the fire around 11 p.m. Wednesday and called 911. The pastor then used a fire extinguisher to snuff out the flames. One of the fires was small but the other was spreading up a wall. Richards said the building would have been destroyed if the pastor had not discovered the fire early. Investigators are now working to determine how the fires were set and by whom. The Bureau of Alcohol Tobacco and Firearms also is investigating.