Notre Dame Cathedral in Paris, France was in flames Monday evening.
Firefighters grappled to control the blaze as the main spire collapsed and smoke billowed from the building.
The church was built in the 12th and 13th centuries, and millions of people came to the heart of Paris to visit every year.
Along with the striking architecture and the famous Rose Window, the Cathedral contains many priceless art pieces. The state of those works is unknown, but the BBC reported Paris firefighters are scrambling to remove as many pieces as they can.
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The church was undergoing renovations, so as many as 16 statues were removed earlier this month.
French historian Camille Pascal told BFM broadcast channel the fire was destroying “invaluable heritage.”
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“It’s been 800 years that the Cathedral watches over Paris,” Pascal said. “Happy and unfortunate events for centuries have been marked by the bells of Notre Dame.”
The vibrant and iconic stained glass windows, both the circular rose windows and the vertical windows, were replaced in the 1960s.
The famed gargoyles are made of stone, and help the structure of the building by keeping rainwater out, the New York Times reported in 2017.
But they were crumbling before the renovation started, and it’s unknown whether they will survive the fire.
Catholic Church relics
Many relics or items that hold great importance in the Catholic Church were housed in Notre Dame.
Among the relics are the Crown of Thorns, which Jesus purportedly wore before being crucified, and a piece of the True Cross, which is said to be a piece of the cross Jesus was crucified upon, the Catholic Herald confirmed on Twitter.
Roof made of a ‘Forest’
According to the official website, the frame of the roof was composed of 1,300 oak trees, which represents more than 21 hectares of forest.
Organs and bells
Notre Dame housed two organs: The Great Organ and the choir organ. There were at least 10 bells.
Statues of saints and other religious figures adorned the halls of the cathedral. Sixteen were removed from the roof earlier this month for renovations — offering a rare glimpse of the top of the cathedral.
*with files from the Associated Press