Chances are it wasn't a 'hateful person' .... just an out of control trouble and addicted person.
I grew up on a reserve in northern Ontario (I won't say where because I like my anonymity). Stuff like this happens all the time. Most of the time, it's not serious and it is just a car or truck that was burnt or a shed or a small building. Most major buildings like offices, hospitals, churches and water plants and waste water plants have round the clock security but often they can't be protected all the time.
You have all sorts of down and out people in these reserves ... alcoholics, addicts, kids hanging out with bags of solvents of all kinds ... and over the past 20 years, really heavily addicted people to powerful opiods and hard drugs (which are far easier to get into communities that big bottles of liquor)
You have no clue how decrepit these northern communities have become due to the influx of opiods and little pill sized drugs that are easy to smuggle into these communities. It's taken communities that were just getting a handle on alcohol addiction in the late 90s and reset everything back to terror by having a large portion of the young population hooked on these terrible drugs now.
Mix into that no employment, no chances for anything, no education, no help and no sympathy from the rest of the country and now have you an entire generation of people who are disconnected from their cultural past, no chance of stepping into the future and the only outlet they have is a tiny little drug that can help them escape this reality for a short time. .... and God, or the Great Spirit help them when they suffer through withdrawal when they can't get their fix.
There is a problem with water shortages and water quality in the north .... but it all stems from communities having to a fight a drug war that is slowly destroying their people.