Maybe because it wasn't a mass shooting. The shooting happened after an altercation between a few people (over 5), who decided to take matters into their own hands and go and shoot the teen. Was the first ever fatal shooting at MOA, but there was one other fatality there that was a stabbing back in 1999.
Three people, including two minors, have been charged in connection with the Friday shooting at Minnesota's Mall of America, the largest shopping center in the US, that left a 19-year-old dead, Hennepin County District Court spokesperson Matt Lehman said.
www.cnn.com
Oh yeah, this news story comes to you from CNN, a news agency you usually deride as not reporting any news.