american john dickas in paris watched from the balcony in shock while on the air with david this afternoon. >> we watched the spire come down about two minutes ago from our apartment. the sky is full of smoke, and you can smell it. just standing on our balcony. you can smell it in the air. i mean, it's happening right in front of us and it's just sickening. >> reporter: the first reports surfaced at 6:50 p.m. paris time. an ominous image of smoke billowing from notre dame. >> there's a fire in the background. >> no! >> 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 engulfed 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 aga

john dickas watching in terror from a balcony as fire engulfed the building. >> there was no questiont 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 such an iconic part of the paris skyline. >> reporter: parisians gathering near the cathedral monday night at moments breaking into holy song. ♪ "ave maria," "hail mary." the fire ripped through the gothic church during holy week, seen as the most important on the christian calendar. >> this is a hugely important place for catholics, for the history of france. and it has been at the center of the story of the parisian people. >> reporter: fire crews saved the iconic towers. precious artwork is also said to be okay. but two-thirds of an entire roof was charred. an emotional president emmanuel macron vowing to rebuild and asking for international help. president trump offered his thoughts on the damage, saying the cathedral is one of the great treasures in the world. janai, kenneth? >> notre

john dickas watched it all from his apartment. >> my partner and i were standing on the balcony, ands moment that she started crying when we watched the spire fall down. it's such like an iconic part of the paris skinline. >> reporter: french president emmanuel macron tearful, called the blaze a terrible tragedy. president trump had these words. >> the fire that they are having at the notre dame cathedral is something like few people have witnessed. it's one of the great treasures of the world, and it's burning very badly. looks like it's burning to the ground. >> reporter: some of the first images from inside notre dame have now been released. the altar where thousands would have flocked to celebrate easter sunday this week now covered in ash. it took 500 fire fighters to battle the flames, at times they were powerless to stop them. >> there's no question. i'll tell you that for me the most heartbreaking moment is when i saw about 20 minutes after i -- i started watching the fire, i saw the -- the ladders go up and the hoses start spraying, and it was just heartbreaking to watch. th

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. 0 fi e. surrounding the cathedral. but at times, powerless against the flames. >> we can see the hoses and some of the spray on that fire.