A public service announcement video shared by nonprofit group Sandy Hook Promise has stirred up significant controversy for its depiction of school children bleeding and screaming for their lives during an active school shooting.

The video begins as a satire of "back-to-school" commercials with young children showing off their new school supplies. After a few frames, screams can be heard in the background as the children promoting their new gear start to use school supplies as defensive weapons. Children jump through broken windows and wait, terrified, in locked classrooms and bathroom stalls.

The video, produced by Sandy Hook Promise, describes its call to action as: "Survive the school year with these must-have back to school essentials."

Sandy Hook Promise, founded by several parents of children slain in the 2012 mass shooting, describes their mission as ultimately preventing gun violence in schools by providing "Know the Signs" training programs at no cost to educators. "SHP is a moderate, above-the-politics organization that supports sensible program and policy solutions that address the 'human side' of gun violence by preventing individuals from ever getting to the point of picking up a firearm to hurt themselves or others," the group says of their mission.

The one-minute long PSA concludes with a call to watch for warning signs of gun violence in schools. "It's back to school time and you know what that means. School shootings are preventable when you know the signs."