A fire alarm reportedly first went off inside Notre Dame Cathedral at 6:20 p.m. Monday, local time. However, according to the official investigation, cathedral staff unsuccessfully searched for signs of a fire for 23 critical minutes, and were unable to determine the reason for the alarm.
It wasn't until a second alarm went off at 6:43 p.m. that a fire was detected in the attic of the centuries-old religious landmark, French officials said Tuesday.
Heitz said the initial alarm, which was looked into by cathedral staff and not firefighters, caused the church to be evacuated but did not lead to the discovery of the fire, according to the Washington Post.
"We are favouring the theory of an accident," Heitz told reporters Tuesday, adding that the investigation into the blaze would be "long" and "complex".
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"In the meantime, the church was evacuated because a Mass had just started a bit earlier," Heitz said.
"Everyone was immobilised by shock for maybe a minute," Vexo said. Minutes later, parishioners and tourists emptied the cathedral, leaving just staff behind.
When he left the building about 20 minutes later, Vexo said there was still no evidence of a fire, adding that he thought it was a false alarm.
Meanwhile, the rector of Notre Dame, Monsignor Patrick Chauvet, told the French radio station France Inter that the cathedral has fire supervisors tasked with checking the attic no less than three times a day to examine the frame, adding: "In terms of security, I doubt we could have done more."
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Meanwhile, in a radio interview on Tuesday, Culture Minister Franck Riester said that the cathedral's treasury of irreplaceable Christian relics — the most priceless being the Crown of Thorns believed to have been worn by Jesus Christ, and the tunic of Saint Louis — were safely stored in the Paris city hall, thanks to a heroic rescue effort led by Catholic priest and chaplain of the Paris Fire Brigade, Jean-Marc Fournier, who bravely ventured into the blazing cathedral to retrieve the holy items.
Philippe Goujon, the mayor of Paris’s 15th district, told reporters that Fournier insisted on being allowed into Notre Dame with the other firefighters.
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French President Emmanuel Macron has vowed to rebuild the cathedral as billionaires and corporations have pledged financial donations to support that effort. France's Heritage Foundation, which has launched a nationwide fundraising campaign for the restoration of the landmark site in the wake of the tragedy, announced that it had already collected 7 million euros to rebuild the cathedral.
The iconic Gothic cathedral, located in the heart of the French capital, became the scene of a devastating blaze on Monday evening. The building was heavily damaged in the fire and two-thirds of the cathedral's wooden roof were destroyed; the main spire and clock collapsed, but the two main towers were saved.