of a tragic new trend in american schools looking out for a shooter, than sacrificing yourself to save your classmates. last week riley howell was killed as he tackled a shooter at the university of north carolina charlottehere's what his parents told cnn last night. >> it is just terrible that more families and communities are going through this, and while i'm angry and i feel embattled, i think at the same time we have to instead of just liolionize, have to galvanize. there just has to be some dialogue from people all around so that we can never, ever, ever let a community have to go through this again. >> boy, we hope that's the case. cnn has obtained cell phone audio capturing the moments police moved on to the shooters in colorado. >> they found him. >> authorities have identified both shooters, one an 18-year-old male, the other a 16-year-old. police initially said the second suspect was a girl, but he identifies as male. both are due back in court to be formally charged friday. >>> the vigil last night actually turned into a demonstration. some people walked out after senator michael bennett and congressman jason crow spoke. >> mental health! mental health! >> mental health i think they're chantin