From the local news article, it looks like the four boys were burning down a shed, and one of them was accidentally splashed with gasoline, which lit. If that’s accurate (which no poster has any way of knowing), then it’s a case of Tragically Stupid.
What are kids doing with gasoline?? I just read the news article that another person linked to - and there is very little info except a police chief saying no one was coerced to be in the shed. How does he know? The kid is comatose!
Even if it turns out to be a prank, I don’t get modern kids who carry around gasoline.