Just to make this clear to everybody: there are no signs at all that this fire was arson. There are multiple explanations for the cause of the fire involving the construction site and some sort of negligence, which seem highly likely to be true.

Besides for lack of evidence of arson and evidence of negligent construction practices, how exactly do you guess one could root out anti-church extremists?

Do you have even the tiniest shred of circumstantial evidence this was intentional?