PARIS: More than 400 firefighters battled massive flames at the Notre-Dame Cathedral, one of the best-known landmarks in the city of Paris, on Monday (April 15) night.

The fire reportedly spread from the attic at around 6.50pm local time. It brought down the cathedral’s towering Gothic spire and roof. It was only after about nine hours that the fire was declared completely under control.

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The cause is still unknown. Meanwhile, investigators are checking if the fire spread from the site of ongoing reconstruction work on the roof, according to a source.

Paris fire brigade chief Jean-Claude Gallet said that the main structure of Notre-Dame can be considered saved and preserved, as well as its two bell towers.

This comes as the first images of the inside of the cathedral emerged.

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Two artefacts, the Holy Crown of Thorns and a tunic worn by 13^th century French king Louis, have been rescued, according to the cathedral’s rector.

Some of the artworks housed in the cathedral have also been rescued and were being put in safe storage.

They will now be transferred to the nearby Louvre Museum, French Culture Minister Franck Riester told reporters.

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Restoring the building will take “years of work”, though French President Emmanuel Macron declared that a “national undertaking” would be launched.