Motorsport is inherently dangerous. The risks of racing high-performance cars at the limit of their capabilities are clear, yet this doesn't make things any less shocking when things go wrong.
This disturbing footage – which we must warn you, does show people being struck by a car – was taken at the Gran Turismo Polonia amateur motorsport event in Poznan, Poland, and depicts a driver losing control of his powerful supercar before mowing through a line of spectators.
Thankfully no one has been reported killed in the accident, though 17 people were injured, four of them seriously, when the driver of a rare Koenigsegg CCX span his car moments after launching it from the start of a drag strip.
Police are now investigating the crash, with the head of Poznan Highway Patrol quoted in La Late News as saying: "There is no doubt that the driver of the vehicle has not mastered it. He had no control of the vehicle."
There is some weight to this suggestion, with additional video footage emerging of the driver spinning the car immediately prior to his off.
Footage of both the accident and the preceding spin can be viewed below, though it's not for the faint-hearted.