Okay, since no one seems to be about to explain: why? Why would you booby trap a rally course? Just being a dick? Some kind of politcal statement? Get out of my country? What?
Too many crash videos on TV. People who are impressed by monster trucks.
There are people who go to races hoping to see crashes. It's only a short hop from that to making one happen.
True story: some years ago I was in a pub, minding my own business, browsing through LJK Setright's 'Flying Colours' - hardly a pocket book and not easy to hide. Some idiot spots the book and feels compelled to tell me how he'd been at Silverstone in 1999 and seen Michael Schumacher crash right in front of him. Now, I'm no Schumacher fan, but I'd draw the line at gloating over him breaking his leg. This guy thought it was funny.