Transcript for Notre Dame Cathedral inferno: 'It was heartbreaking to watch'
But we do begin this week with those devastating images, the heartbreak from Paris tonight. Notre dame cathedral going up in flames. The first call shortly before 1:00 P.M. Eastern today, 6:50 P.M. Paris time. That fire surrounding the spire. Then the fire then advancing, kreeching across that roof. Then, in engulfing the spire and as millions around the world were watching, that iconic spire then collapsing on live TV. Fears growing more of that cathedral coming down. Crowds gathering in the streets below watching the heart of Paris burn. A short time ago, the mayor of Paris on the new evacuations tonight, fear there could be another collapse. The mayor revealing they now have drones inside the cathedral, monitoring the fire and what they see is, quote, terrible. ABC's David Wright is on the scene in Paris tonight. Reporter: Tonight, an icon of Paris, the very heart of the city, in flames. The whole world watching in disbelief. The spire of the 850-year-old notre dame cathedral collapsed, caving in the roof, engulfing the heart of the iconic church in flames. Eyewitness John dickas watching in terror. There's no question that was the most horrifying moment. My partner and I were standing on the balcony watching, that was the moment that she started crying, when we watched that spire fall down. It's just -- you know, it's an iconic part of the Paris skyline. Reporter: The first reports sure faced at 6:5 P.M. Paris time. An ominous image of smoke seen billowing from notre dame. There's a fire in the background. Reporter: Then, to the horror of onlookers, the first flames burst through the ceiling. The inferno quickly out of control. The cause unknown, but it again ulfed scaffolding from a $6 million renovation project. Authorities are investigating whether a construction worker may have accidentally sparked the blaze. Crowds of onlookers transfixed, this building has withstood revolutions and two world wars. The history of France written in stone. Tonight, a stunned silence. Many are in tears. 400 firefighters rushed to the scene. Surrounding the cathedral. But at times, powerless against the flames. We can see the hoses and some of the spray on that fire. It certainly seems to be overwhelming the authorities there on the ground. There's no question. I'll tell you, for me, the most heartbreaking moment was when I saw, about 20 minutes after I started watching the fire, I saw the ladders go up and the hoses start spraying and it was just -- it was just heartbreaking to watch. The ladders were not tall enough. The hoses were not strong enough. Reporter: As the fire ferociously spread, authorities scrambled to try and rescue priceless art and catholic relics from the 850-year-old tonight, the mayor said the process is partially successful. Notre dame, the most visited location in all of France, 30 million tourists a year. French president Emmanuel macron said the fire took part of everyone in France with it, adding, our lady of Paris is in flames. It's quite striking here to see all the parisians who come here to gather to mourn. I don't know what to say. For me, it's the most beautiful monument in Paris. Reporter: Tonight, as darkness fell and the fire continues to rage, the roof and the spire are destroyed and the race is on for authorities to save what they can. So, let's get the latest on that effort. David Wright live from notre dame cathedral in Paris. And David, I know the mayor revealing a short time ago that they do believe they've been able to save key parts of this cathedral? Reporter: That's right, French authorities believe that they have managed to save those two iconic towers. No word yet on the stained glass. You can see the building there behind me in darkness now, but as from where I'm standing, you can see fire crews continue to pour water on it. The mood here in Paris is one of great sadness, but also resolve. The French president saying tonight, we will rebuild. David? David, thank you.
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