Fire crews have put out an early morning blaze at Holy Name Cathedral, a 134-year-old Chicago landmark and the seat of Cardinal Francis George.
Flames shot through the church's blackened roof for about an hour before they were replaced by plumes of white smoke. The fire was struck at around 8 a.m.
There were no injuries.
George was inside the church shortly after the blaze was out to survey the damage.
Church officials say there was extensive water damage and fire officials were pumping water out of the basement. The fire also burned gaping holes into the roof.
Chicago Archdiocese Chancellor Jimmy Lago expects the church to be closed for months.
He says sacramental records that were kept in a fire proof vault in the rectory are believed to be safe.