Smoke and fire is seen leaping from the top of Notre Dame, the iconic Paris cathedral. Videos shot by people show the blaze engulfing the spire between its bell towers.
The fire broke out in the cathedral on Monday afternoon, a Paris fire department confirmed, adding that a major operation to tackle the fire is underway.
The causes of the incident remain unknown so far.
The Medieval cathedral is one of the main attractions of the French capital, seeing 12 million tourists a year.
The incident took place as the jewel of the Gothic architecture was undergoing a major overhaul costing € 11 million ($ 12.43 million), with the renovation works being expected to be finished around 2022.
Last week, 16 bronze statues representing 12 apostles and four evangelists from the New Testament were lifted off the spire of the cathedral by crane. Some scaffolding can now be seen close to the flames leaping out near the cathedral’s spire.
The spire itself was made of wood and covered with lead has long been in a bad shape as the elements of the construction dating back to the mid-nineteenth century have been damaged by weather, pollution and time.
The cathedral was being built from 13th to 15th century.