Firefighters are on the scene at Notre-Dame Cathedral in Paris after a huge fire broke out in the landmark building on Monday afternoon.
Video footage on social media showed a large fire ravaging the roof and spire as smoke billowed from the building in central Paris.
The gothic cathedral dates back to the 1100s and is famous as the setting of the classic Victor Hugo novel, The Hunchback of Notre-Dame. It is also one of the the city's most visited tourist attractions.
France 2 television reports that police are treating the fire as an accident, Reuters news agency reports, but officials are yet to confirm the cause of the blaze.
They said the area around the cathedral has been cleared as firefighters tackle the blaze.
"A terrible fire is underway at Notre-Dame Cathedral in Paris," Mayor Anne Hidalgo said on Twitter.
Extensive renovations were being carried out on the building, with scaffolding surrounding it in parts.
The deputy mayor of Paris, Emmanuel Gregoire, says the cathedral has suffered "colossal damages" while a cathedral spokesman told the Guardian that the entire wooden interior was on fire and likely to be destroyed.
Malcolm McLoughlin, Associate Pastor of Trinity International Church in Paris, told Christian Today he was "heartsick" at the devastation caused by the fire to such a beloved building.
"We are heartsick at this terrible loss and are grieving with the people from Paris and around the world. Notre Dame Cathedral is iconic and deeply loved by the millions who visit it each year," he said.
"We as followers of Jesus are praying for comfort for the grieving, strength for the firefighters, and wisdom for our leaders. May this catastrophe draw us closer to our Lord Jesus."
Firefighters in Paris say there is a fire at Notre-Dame Cathedral. https://t.co/HHUXgZE4x1— Twitter Moments (@TwitterMoments) April 15, 2019