Investigators are trying to determine the cause of two fires in eastern Iowa.The State Fire Marshal’s office will try to find the cause of the fire that destroyed the St. Paul Lutheran church in Luzerne. The church burned to the ground Friday and parishioners held services yesterday at the fire station. It’s the only church in the small community. The Fire Marshal’s office is also looking into a fire that hit a business in Manchester. The fire in downtown Manchester Sunday caused extensive damage to the Marantha bookstore and also damaged two nearby businesses. Fire departments from five surrounding communities help Manchester firefighters put out the fire.