As soon as the firefighters managed to escape two of the 850-year-old cathedral's towers, the rumors that the fire was caused by a carelessness of the workers involved in the restoration of the building began to escape .

However, a French police official told the Associated Press that the fire was triggered by a spark. About 40 restoration workers are also under investigation, while 50 investigators are considering the issue, although the situation is problematic as the building is still unsafe.

French newspaper Le Parisien reported that the fire alarm originally dropped after 6 o'clock in the afternoon, but security cameras failed to find the location. Le Parisien also added that the flames may have been caused by an electronic fault on a lift.

Officials said the fire alarm fell again after 20 minutes, but the cameras could not yet detect the flames. Then, around 6:43, the state of emergency was announced as the flames were visible.

In less than an hour, the fire swept the back of Notre-Dame. After the situation was under control, François-Hernand Pinault donated 100m euros and Berndard Arnault 200m euros. Inside Wednesday, the French government secured about 850m euros donations from giant companies, wealthy French families, and international corporations to rebuild the famous cathedral.

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