Transcript for Student heroes helped save lives in Colorado shooting
But first we'll begin with new details on that fatal school shooting in Colorado. Overnight protests erupting at a vigil for the victims as we learn more about the hero students who helped stop the gunman. Our chief national correspondent Matt Gutman is in highlands ranch, Colorado, with the good morning, Matt. Reporter: Good morning, robin. That was one of two vigils and at that one that you just mentioned the students seemed to rebel at the political tone taken by organizers chanting mental health. Instead they wanted the focus to be on the three students who tackled that primary shooter stripping him of his gun and, of course, one of those students paying for his courage with his life. Reporter: A sdrij toll remember the victims boiling over in anger. Frustrated students stalking out of the high school demanding to be heard. The event featured politicians like presidential hopeful Colorado senator Michael Bennet and gun control advocates speaking to a packed gymnasium but the tone shifted with students and their parents protesting politics and blaming the press. This can be an incredibly divisive or painful awful time or it can be a time where we come together. Reporter: It spilled into the hallways. Students chanting. This anger coming as a community grapples with a tragedy. 18-year-old Kendrick Castillo was killed after being the first person to rush the shooter. Complete disregard for his own safety. He was immediately there to respond. He was immediately on the shooter and he was ready to end the threat. Reporter: Witnesses say Castillo pinned 18-year-old Devon Erickson to the wall. That's when Brendan bialy, a marine recruit also pounced. There was fear. I still look back the ait and still feel a bit of fear but after that point it is just doing what I thought I should do. Reporter: Just three days shy of graduation, Kendrick was a tinkerer into robotics would worked on his father's car and told his dad if he ever encountered a shooter he'd fight. When I see the people that he saved, it makes me happy and I know that my son wouldn't have had it any other way. But as any parent will tell you, you know, it's a heck of a trade-off. Reporter: Students tried to resuscitate him but it was too late. Joshua Jones also had leapt on the shooter paying for it two bullets. He's one of nine people shot. Several still hospitalized this morning. I got to see two heroes, two awesome people jump into action without any hesitation and I was more than lucky to join them in doing that action. Reporter: As that gunfire rang out one 15-year-old student immediately started texting his father saying, dad, I love you just in case. 36 hours later he can't get the sound of that lockdown alarm out of his head. Or that sense of fear. No matter what, what you went through, there's -- there is no possible way to justify taking what you're feeling out and inflicting it on other people. Reporter: Like many at the school he knew both of the suspects. Erickson appearing in court. That fuchsia stripe of hair bobbing when he nodded to the judge. He and his 16-year-old alleged accomplice face up to 30 charges including for murder. Now, that young man, that 15-year-old was one of over 1800 kids that made it out alive completely unharmed but says he's not okay. He is emotionally scarred and he says else's concerned about the normalization after these shootings. Now, one of the things the police investigation is now focusing on is how those two students obtained handguns when in Colorado it is illegal to have or possess handguns for anyone under the age of 21. Robin. All right. Matt, thank you.
This transcript has been automatically generated and may not be 100% accurate.