Mayor: 'Artwork in safe place'

Emergency teams managed to rescue valuable artwork and religious items, including what is said to be the crown of thorns worn by Jesus before his crucifixion, which were stored inside the cathedral built in the 12th and 13th centuries.

A tunic, which King Louis IX is said to have worn when he brought the crown of thorns to Paris, was also saved.

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"We had a chain of solidarity, especially in saving the works of art... [They] were able to be saved and put in a safe place," said Paris Mayor Anne Hidalgo. "This is a tragedy for the whole world... Notre-Dame is the entire history of Paris."

Historian Camille Pascal told French broadcaster BFMTV that "invaluable heritage" had been destroyed. "Happy and unfortunate events for centuries have been marked by the bells of Notre-Dame. We can be only horrified by what we see."