Investigators have found burnt cigarettes inside what remains of Notre Dame — but the cause of themassive fire at the cathedralis still unconfirmed.

The church was undergoing a $6.8 million restoration project when the fire erupted, and the owner of Le Bras Freres, the company responsible for the construction scaffolding around the roof and spire, has admitted that his employeesdid “sometimes” smokeon the job, flouting the rules, Reuters confirms.

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Notre-Dame Cathedral fire

Initial reports indicated the fire started in Notre Dame’s attic, which has a wooden framework, and spread across the roof and up the 300-foot spire. The attic is nicknamed “the forest” for its dense timber structure, says Paris public prosecutor Rémy Heitz. There are also no sprinklers or fire-blocking walls installed in this area, as there are elsewhere in the historic building.

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Notre-Dame Cathedral

Paris Fire brigade officials reportedly stated at the time that the fire was“potentially linked” to the renovationof the building, according to theChicago Tribune.But investigators stated on Wednesday that they could not yet determine if the workers’ cigarettes were the cause of the fire.

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Last week, another theory surfaced from an Associated Press source stating thatfire may have been tied to a short circuit, according to CBS News. The local Le Parisian newspaper reported that a computer glitch or an issue with temporary elevators being used in the restoration may have been to blame.

The magnitude of the fire was likely due to theperiod of time it burned undiscovered.

The first alarm went off at the church at 6:20 p.m. Checks were carried out at that time, Heitz confirms, but no fire was found. It wasn’t until 23 minutes later, when a second alarm sounded, that the blaze was located, according to theNew York Times.By that time, it could not be contained.

Notre Dame fire

The person sent to check on the location where the alarm sounded went to the wrong part of the cathedral, despite the fire detection system indicating the correct spot, according to a source close to the investigation.

Despite the destruction, the main part of the structure has been saved and fundraising for the effort to restore and rebuild the 850-year-old church has already topped $1 billion, thanks to massive donations from wealthy French citizens including Francois Pinault,Salma Hayek’s husband, who pledged $100 million euros, and LVMH headBernard Arnault, who will contribute $200 million euros.

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Cathedral of Notre-Dame of Paris on fire, France - 15 Apr 2019

The Catholic church is a world-famous landmark for the French capital, second only perhaps to the Eiffel Tower, and draws about 13 million visitors per year. It has been a center of religious and cultural life there since it was completed around 1365.

The building has weathered its share of tragedies over the years. During the French Revolution, it was looted and desecrated, according toThe Guardian, before Napoleon began renovations in the mid-1800s. The cathedral also survived both world wars — including the Nazi occupation of Paris in World War II.

It has undergone even more restoration and cleaning projects over the years, including major efforts in 1963 and 1991.

source: people.com