Flames rise from Notre Dame Cathedral as it burns in Paris, Monday, April 15, 2019. [Photo: AP/Thibault Camus]

The soaring spire of Notre Dame Cathedral in Paris has collapsed in flames, and a church spokesman says the entire wooden interior of the 12th century landmark is burning and likely to be destroyed.

Firefighter douse flames billowing from the roof at Notre-Dame Cathedral in Paris on April 15, 2019. [Photo: AFP]

A massive fire engulfed the roof of the cathedral in the heart of the French capital on Monday afternoon as Parisians watched in horror.

Notre Dame spokesman Andre Finot told French media: "Everything is burning, nothing will remain from the frame."

Flames and smoke rise from Notre Dame cathedral as it burns in Paris, Monday, April 15, 2019. [Photo: AP/Thibault Camus]

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 isn't yet known, but scaffolding could be seen on the roof of the burning structure, as the spire was undergoing renovation.