ST. LOUIS – A two-alarm fire led to significant damage Saturday afternoon at a north St. Louis church.

The fire happened at a church known as “The Sanctuary” at the intersection of Rosalie Street and Red Bud Avenue in the O’Fallon neighborhood.

Investigators said the church has been vacant and out of use for several years, but one person was inside when it caught fire. One person in the basement kicked out some windows and got out of the building with some assistance from firefighters.

The St. Louis Fire Department is working to determine the cause of the fire, and it’s unknown if the man inside the church basement started it.

David Neighbors of the St. Louis Fire Department told FOX 2 that the building is in unstable condition. Because the building is unstable, it’s not clear if firefighters will be able to go inside later to look at the damage.

“We will be extinguishing this from the exterior for the safety of our members,” said Neighbors. “Our investigation unit is here, with the stability of the building being the way it is, it’s unsure just exactly how much of the investigation they’ll be able to get inside and do.”

Throughout its history, the church has been home to the North Campus Partnership, ran by former St. Louis Alderman Antonio French.

Additional details are limited. FOX 2 will update as more information becomes available.