A fire Saturday afternoon damaged a former Catholic school building that is being converted into senior housing units.

The Sanford Fire Department was called to the former St. Ignatius School on St. Ignatius Street around 3:45 p.m. to put out a fire that started outside and spread into the building, according to fire officials.

Crews from Sanford and surrounding communities were able to stop the fire from spreading and no one was injured, fire officials said. The cause of the fire remains under investigation.

The former school building and St. Ignatius Church, located just off Main Street, are being renovated by the Roman Catholic Diocese of Portland into 66 apartments for senior citizens. The apartments are scheduled to open by fall.