If it was a gun free zone, was the assailant using one of those blue dummy guns? Or one with an orange plug in the barrel?
As far as letting people know what's going on, relying on word of mouth is faulty logic anyway, but if that was their only means of getting the word out besides the email/text alerts then they needed to provide more time for the word to spread. We had a lockdown drill at our elementary school and I don't think they even brought in anybody to be the armed intruder, but it was advertised all over the place with lots of explanation of what would be happening for 2 weeks prior to the event. Granted ours was an elementary school and this happened in a college, but it's just as frightening if not more so for the college kids. They definitely needed a better notification system. Very good for whoever planned this that there were not students/faculty allowed to carry or they could have had more serious problems than students shaken up over the ordeal!