Firefighters tackle the blaze as flames and smoke rise from Notre Dame cathedral as it burns in Paris, Monday, April 15, 2019. Massive plumes of yellow brown smoke is filling the air above Notre Dame Cathedral and ash is falling on tourists and others around the island that marks the center of Paris.

Flames and smoke rise from Notre Dame cathedral as it burns in Paris, Monday, April 15, 2019. Massive plumes of yellow brown smoke is filling the air above Notre Dame Cathedral and ash is falling on tourists and others around the island that marks the center of Paris.

Notre Dame cathedral is seen burning in Paris, Monday, April 15, 2019. 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.

A fire fighter uses a hose as Notre Dame cathedral is burning in Paris, Monday, April 15, 2019. 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.

Flames rise from Notre Dame cathedral as it burns in Paris, Monday, April 15, 2019. Massive plumes of yellow brown smoke is filling the air above Notre Dame Cathedral and ash is falling on tourists and others around the island that marks the center of Paris. (AP Photo/Thibault Camus)

Notre Dame cathedral is burning in Paris, Monday, April 15, 2019. Massive plumes of yellow brown smoke is filling the air above Notre Dame Cathedral and ash is falling on tourists and others around the island that marks the center of Paris. (AP Photo/Lori Hinant)

Notre Dame cathedral is burning in Paris, Monday, April 15, 2019. Massive plumes of yellow brown smoke is filling the air above Notre Dame Cathedral and ash is falling on tourists and others around the island that marks the center of Paris. (AP Photo)

Plumes of smoke rises from Notre Dame cathedral burning in Paris, Monday, April 15, 2019. Massive plumes of smoke fills the air above Notre Dame Cathedral and ash is reported to be falling on tourists and others around the island that marks the center of Paris. (AP Photo)

Flames rise from Notre Dame cathedral as it burns in Paris, Monday, April 15, 2019. Massive plumes of yellow brown smoke is filling the air above Notre Dame Cathedral and ash is falling on tourists and others around the island that marks the center of Paris. (AP Photo/Thibault Camus)

Flames rise from Notre Dame cathedral as it burns in Paris, Monday, April 15, 2019. Massive plumes of yellow brown smoke is filling the air above Notre Dame Cathedral and ash is falling on tourists and others around the island that marks the center of Paris. (AP Photo/Thibault Camus)

A firefighter tackles the blaze as flames and smoke rise from Notre Dame cathedral as it burns in Paris, Monday, April 15, 2019. Massive plumes of yellow brown smoke is filling the air above Notre Dame Cathedral and ash is falling on tourists and others around the island that marks the center of Paris.