Police blocked off a section of Old St. Patrick Street in Ottawa's Lowertown neighbourhood Thursday after part of a church collapsed.

Father Drouin, who has been parish priest at Ste-Anne Catholic Church for 29 years, told CTV Ottawa the collapse started when a wall in the attic gave way, causing it to fall through the ceiling of the francophone parish, located at 528 Old St. Patrick Street.

Drouin said two nuns were in the church 10 minutes prior to the collapse. No one was inside at the time of the incident.

However, an organist just missed the collapse and reported seeing a cloud of dust when she arrived.

Now, Drouin and two nuns who lived in the rectory are without a home.

Drouin said city engineers have told him it could be several months before the church can be used again.

St-Anne Catholic Church was built in 1873.