This is the image they're showing of the "assault weapon:"
I held one of these in my hands just last week. It shoots .22 rimfire! The "suppressor" that they're all freaking out about is a fake. It's just a barrel shroud. It has absolutely ZERO suppression capabilities.
There have been reports from locals that the IEDs they found were either inert or non-functional. This guy was a wannabe. He might've harmed some students, but in the end, he was a coward who killed himself when faced with the possibility of armed resistance.
It appears that he wanted to, but did not have the ability to pull it off. We see it in would be serial killers as well. It is only those that are smart enough, or lucky enough, that do not get caught after the first one or two, that make the headlines.
Those that get caught or stopped do not make the headlines.