A massive fire broke out at the Notre-Dame Cathedral in Paris on Monday, first according to social media and later reported by news outlets. The fire set off an alarm in the cathedral around 6:30 p.m. Paris time, after which tourists and people in the area were quickly evacuated. The BBC reports that officials have said “that it could be linked to renovation work.”

A French official has stated that, despite the destruction, “both towers of the cathedral are safe.” There were around 400 firefighters still working on containing the blaze when night fell in Paris.

Since the fire began, the iconic central spire of the cathedral has collapsed.

French citizens gathered on bridges and in the streets to watch and mourn the building as the fire continued to burn.

French President Emmanuel Macron wrote on Twitter that he was “sad to see this part of us burn tonight.”

Anne Hidalgo, the mayor of Paris, wrote that it was a terrible event and urged people to respect the perimeter set up by firefighters.

Construction on Notre-Dame de Paris, its official name, began in the 12th century, and the cathedral has been restored several times since.

Originally published in Vogue