The drill is called Vigilant Guard. Actors Needed for Vermont's Largest-Ever Disaster-Preparedness Drill | Arts News | Seven Days | Vermont's Independent Voice
They seem to be more in your face with their drills turning into live events. On 9/11 they were conducting a drill of planes flying into buildings. They were conducting a drill the day of London bus bombing on 07/07/05. I heard they were conducting a drill during the San Bernardino shooting on 12/02/15. During the Pulse nightclub shooting on 06/12/16 they were also conducting a drill in the area. I'm sure you could compile a lengthy list.