A few days ago, in one of the several Ferguson threads, I posted a report of an officer involved shooting in St. Louis City.
The story was a man went into a store with a knife and was threatening people, then he confronted the police who responded, charged them and was shot to death.
There is a video from an eyewitness who recorded the confrontation and shooting.
WARNING: Although this was taken from about 25ft away or more and you can't see blood or anything, it's a disturbing video.
http://youtu.be/j-P54MZVxMU