Photo: @AirForce_Carl/Twitter

UPDATE 3:16 p.m.

A catastrophic fire engulfed the upper reaches of Paris' soaring Notre Dame Cathedral as it was undergoing renovations Monday, threatening one of the greatest architectural treasures of the Western world as tourists and Parisians looked on aghast from the streets below.

The blaze collapsed the cathedral's spire and spread to one of its landmark rectangular towers, but Paris fire chief Jean-Claude Gallet said the church's structure had been saved after firefighters managed to stop the fire spreading to the northern belfry. The 12th-century cathedral is home to incalculable works of art and is one of the world's most famous tourist attractions, immortalized by Victor Hugo's 1831 novel "The Hunchback of Notre Dame."

The exact cause of the blaze was not known, but French media quoted the Paris fire brigade as saying the fire is "potentially linked" to a 6 million-euro ($6.8 million) renovation project on the church's spire and its 250 tons of lead. The Paris prosecutors' office ruled out arson and possible terror-related motives, and said it was treating it as an accident.

UPDATE: 11:20 a.m.

A massive fire engulfed the roof of Notre Dame Cathedral in the heart of the French capital Monday, shooting up its long spire and sending thick plumes of smoke high into the blue sky as tourists and Parisians looked on aghast from the streets below.

The cathedral is home to incalculable works of art and is one of the world's most famous tourist attractions.

The cause of the blaze was not known, but the Notre Dame spokesman said the whole frame of the cathedral was burning

As Paris firefighters battled the blaze, part of the spire of the 12-century monument collapsed.

Paris police said there were no deaths so far and the origin of the fire was unknown. French media quoted the Paris fire brigade saying the fire is "potentially linked" to a 6 million-euro ($6.8 million) renovation project on the church's spire and its 250 tons of lead.

Flames shot out of the roof behind the nave of the cathedral, among the most visited landmarks in the world. Sights of the flames stopped passers-by in their tracks along the Seine River that passes beneath the cathedral.

French President Emmanuel Macron postponed a televised speech to the nation because of the stunning blaze and was going to the cathedral himself.

Macron's pre-recorded speech was set to be aired Monday evening, to lay out his long-awaited answers to the yellow vest crisis that has rocked the country since last November.

Associated Press reporters at the scene saw massive plumes of yellow brown smoke filling the air above the Cathedral and ash falling on the island that houses Notre Dame and marks the centre of Paris.

Paris Mayor Anne Hidalgo is in despair at the "terrible fire." Hidalgo said in a Twitter message that Paris firefighters are still trying to limit the fire and urged Paris citizens to respect the security perimeter that has been set around the cathedral.

Hidalgo said Paris authorities are in touch with Paris diocese.

ORIGINAL 10:40 a.m.

Paris police say there is a fire at the city's Notre Dame cathedral.

BBC News is reporting the fire may be linked to renovation work on the 850-year-old Gothic building.

Fire crews are working to tackle the blaze and have evacuated an area surrounding the fire. 

More to come...

Update #NotreDame les flics évacuent le toit va tomber j'ai chaud depuis ma fenêtre pic.twitter.com/Qzp5H7gLhx

— Rox 🐍🌟 (@yellow__rox) April 15, 2019