PARIS - With its iconic cathedral scorched but still standing, France on Tuesday was contending with the aftermath of a fire that gutted a symbol of the nation, and which authorities said had probably started by accident.
On a Paris day on which smoke had cleared from the sky, France began its investigation into what had gone wrong, looking both into what triggered the Notre Dame inferno and into whether the stone facade of the church remained structurally strong.
From certain angles on Tuesday, it was almost possible to look head-on at the front of church, see its two rectangular bell towers and carved statues and imagine that all was intact. Much of the valued art and relics had been saved. Even the ornate, centuries-old stained glass windows remained in place, seemingly immune to the previous day's flames.
But that belied the somber accounting of all that had been lost, and how the religious and architectural landmark at Paris's center had been altered. The church's trademark steeple, part of the Parisian skyline since the mid-1800s, had been swallowed in the flames. Char and smoke marks licked portions of the walls. And the roof - constructed with centuries-old wood - had been destroyed like tinder, leaving gaping holes that let sunlight shine into the cathedral Tuesday.
Officials warned that Notre Dame may still have gravely dangerous vulnerabilities, especially in the soaring vault. But a few government officials ventured inside, and camera footage showed charred rubble in front of the still-intact pews.
"We will stay at the bedside of the cathedral," France's interior minister, Christophe Castaner, said after walking inside, speaking of Notre Dame like a wounded patient.
From around the world, donations poured in for reconstruction, and both Parisians and tourists lined the Seine, bearing witness at bridges where police cut off access to the site.
Castaner said more than 500 firefighters had been mobilized Monday to help extinguish flames that had left city skyline cloaked in smoke. But questions remained about whether there had been initial warning signs.
Paris Prosecutor Rémy Heitz laid out a timeline in which a first alarm went off at 6:20 p.m., but no signs of fire were initially found. Only when a second alarm went off - 23 minutes later - was fire detected.
"In the meantime, the church was evacuated because a Mass just started a bit earlier," Heitz said.
Officials said they do not suspect foul play, and Heitz said were no indications that the blaze was started deliberately. Officials plan to interview people from the five companies that were doing renovation work at the site. Before the fire, part of the Gothic structure had been encased in scaffolding.
The cathedral was built over centuries starting in 1163. It was partially consumed in just hours Monday, as thousands of Parisians stood sentinel on the banks of the Seine, singing "Ave Maria" and weeping at the sight.
"Parisians lose their lady," read one French headline. In Strasbourg, the city's great cathedral tolled its bell for 15 minutes Tuesday morning in solidarity.
Speaking on French radio early Tuesday, Culture Minister Franck Riester said many significant works of art in the cathedral were saved and that Notre Dame's organ had survived the flames - whether it had suffered water damage was still to be determined. Riester also confirmed preliminary reports from firefighters that they had been able to save the church's two most hallowed relics: the crown of thorns Jesus is said to have worn and a tunic worn by Saint Louis, a 13th-century French king.
The objects were being transferred from Paris City Hall to the Louvre, officials said.
"It was necessary to bring them out through the smoke," Paris Fire Commander Jean-Claude Gallet told BFMTV. He said firefighters rushed into the chamber of the cathedral at the height of the fire to make the rescue.
The cathedral's most precious stained-glass rose windows, an ensemble that dates to the 12th and 13th centuries, are also likely intact, said André Finot, a cathedral spokesman.
"It's a bit of a miracle. We're very relieved," he told BFMTV.
Vittorio Sgarbi, a Rome-based art historian, said that Notre Dame, even before the fire, had been an architectural mish-mash - some parts original, but many parts replaced.
"This is going to be a fateful event in the story of a non-authentic building, a sort of laboratory," Sgarbi said.
Even as the fire still burned, France was making plans to reconstruct the church. French Prime Minister Edouard Philippe convened a crisis meeting. French President Emmanuel Macron visited the devastation during the night and vowed to rebuild.
The effort was supported by Pope Francis, who called the fire a "catastrophe" and described on Twitter a desire that the damage would be "transformed into hope with reconstruction."
From around the world, money poured in for reconstruction. Some donors said the outpouring showed the importance of a building that had become emblematic of faith, art and of France itself.
On Tuesday morning, Paris Mayor Anne Hidalgo floated the idea of an "international donor's conference" that would unite philanthropists and restoration experts in Paris to raise money for targeted purposes in rebuilding Notre Dame.
French luxury magnate François-Henri Pinault declared that his family would dedicate about $113 million to the effort. Hours later, the family of Bernard Arnault, chief executive of the LVMH luxury conglomerate and the richest man in Europe, pledged a gift of $226 million. By Thursday evening in Paris, private pledges had topped $700 million.
One expert said the reconstruction effort could take decades.
Several French people who had started smaller crowdfunding campaigns described on Tuesday being moved by the gestures.
"I am not religious myself; I'm an atheist," said Charles Gosse, 23, a business school student who launched an online funding campaign and quickly raised $27,000. "But this is beyond religion. It is a national monument like the Eiffel Tower and the Arc de Triomphe."
France, though officially secular, remains a devoutly Catholic nation, and many of the people who came to see the remnants on Tuesday said they were prompted by their faith. This is the holiest week of the year on the Christian calendar.
"I'm a believer," said Carine Mazzoni, 48, a lawyer who said her son was confirmed at Notre Dame. "It's Easter week. It's a symbol of Paris and a Catholic symbol. It's the history of the world that's united in this building."
Longtime city residents said they had a hard time comprehending the destruction.
"I've been a Parisian for 62 years," said city-native Alix Constant, a medical secretary. "When I saw the images of the fire, I had the need to see it with my own eyes. And even more so because I'm a practicing Catholic."
There were no deaths, but two police officers and one firefighter were injured, officials said.
In their account of the fire and rescue effort, firefighters told local media that after the first call came in, they had to get through rush-hour traffic clogging the banks of the Seine.
The flames quickly spread from the top level of the nave, eating up one beam, then another, in a vast portion of the roof that has been called "the forest" because each massive support was carved from an entire tree. The 750-ton spire, which was originally constructed in the 13th century and rebuilt in the 19th out of oak covered with lead, toppled shortly before 8 p.m.
At the height of the effort to combat the blaze, which raged for about nine hours, firefighters trained 18 hoses on the church, according to local media accounts. They pumped water straight from the Seine, the grand river that traverses Paris and closely abuts Notre Dame.