There have been something like 180 cases of arson...
https://www.foxnews.com/world/australia-brush-fire-24-charged-new-south-wales
Here is a link to an ABC (the national broadcaster in Australia) article today, debunking that claim:
https://www.abc.net.au/news/2020-01-08/fires-misinformation-being-spread-through-social-media/11846434
The article refers to the above claim and says the actual number of people charged is 24, and not all of those charged “...managed to spark large blazes”.
Of course it is not just Fox News giving false info. Progressive news sites have been just as bad, if not worse, with their garbage maps:
https://www.abc.net.au/news/2020-01-08/misleading-fire-maps-go-viral-during-australian-bushfire-crisis/11850948
It is annoying, because the truth is very bad, so why undermine it with falsehood and exaggeration.