I just found out about this on my lunch break and it's so upsetting. From what I read it sounds like they were doing renovations in the spire and think the fire is linked to the renos they were doing. I can't event imagine how Paris is feeling right now about the loss of the Cathedral. They're saying that by the time the fire is under control that there likely won't be anything left. It's a very sad day for France and the rest of the World.

Cheers,
Ember