Sources: http://www.nascar.com/2009/news/headlines/cup/04/26/post.race.fans.injured.talladega.cedwards/story_single.html#page2 http://www.telegraph.co.uk/sport/motorsport/5231092/Nascar-investigate-Carl-Edwards-crash-after-seven-spectators-injured.html
A collision between two cars (driven by Brad Keselowski and Carl Edwards) at a NASCAR race led to Edwards’ car crashing into perimeter fencing on the final lap of the Sprint Cup Series Aaron’s 449 race at the Talladega Superspeedway (Alabama) on Sunday 26th April.
Seven spectators were struck by flying debris from the collision and suffered non-life-threatening minor injuries (including a suspected broken jaw and minor contusions / fractures). An additional spectator sitting in the same grandstand also suffered chest pains after she had witnessed the incident (possible primary psychiatric damage anyone?), while Edwards himself was able to jog from his car across the finishing line.
According to both a NASCAR official (Jim Hunter) and the medical director of the track (Dr. Bobby Lewis), it was not possible to say with any certainty whether the pieces of debris came from Edwards’ car or from the fence that absorbed the impact, what is important though is that the retaining fence stayed intact and kept the wreckage of the car on the race track. Without this fence, there is no doubt that the injuries could have been fatal.
See also critical reaction from Joe Menzer (from NASCAR.com) who suggests that further safety changes need to be made in order to make the track safe: http://www.nascar.com/2009/news/opinion/04/26/one.menz.jmenzer.talladega.safety.cedwards/story_single.html#page2
You can see a Youtube clip of the crash here: