A fire has taken hold of the famed Notre Dame cathedral in Paris, causing the spire to collapse.
Thick plumes of smoke are billowing into the air and large flames are engulfing the building.
Dramatic footage posted to Twitter showed the moment the medieval spire collapsed, as stunned Parisians watched on in disbelief.
Officials said the blaze could be related to renovation works being carried out at the cathedral.
The peak of the church is undergoing a 6 million-euro (A$9.4m) renovation project.
No injuries have been reported.
A spokesman said the entire wooden frame of the cathedral would likely come down, and that the vault of the edifice could be threatened too.
'Everything is burning, nothing will remain from the frame,' Notre Dame spokesman Andre Finot told French media. The 12th-century cathedral is home to incalculable works of art and firefighters have been seen trying to remove the art.
French President Emmanuel Macron postponed a televised speech to the nation because of the blaze. Taking to Twitter, the president said he is 'sad to see this part of us burn'.
Paris Mayor Anne Hidalgo described it as a '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.
The Mayor added Paris authorities are in touch with Paris diocese.
The medieval cathedral was completed in the 13th century and today, with its towers, spire, flying buttresses and stained glass, is considered a feat of architecture as much as a religious symbol.
Located in Île de la Cité, a small island in the middle of the city, the cathedral is one of Paris' most popular attractions, drawing an estimated 13 million visitors a year.
The fire comes just days before the Easter Sunday and the end of Lent.
More to come…