The video was taken by a camera in a restaurant across the street from the shooting.
It happened Wednesday afternoon in the parking lot of a McDonald's on Clark Street near Pratt after the gunman exchanged words with a group of young people.
When you zoom in, you can see the gunman raise his weapon and open fire.
Markeyo Carr, 17, was killed.
A 14-year-old girl and two other teenaged boys were wounded.
