> This assumes that cops would shoot canisters near the fire, which is
> dubious at best. Unless you want to set a lot of fires, but this
> sounds like burning a village to save it.
No. One fire in the middle of a large area clears out the whole place. You don't have to shoot the tear gas near the fire, all the air around the fire gets sucked up from the heat and fresh air gets pulled in to replace it.