Here's the scenario. A tornado strike in Englewood. Mass casualties. Over 100 volunteer actors play the walking wounded. One of the actors even plants himself in a tree.
The reality here is that a former row house was set up to simulate apartments with a parking garage. The fire department then bashed in some walls. It becomes a live exercise in a truly fragile building, about as close to the real deal as you can get, right along with frantic emergency calls.
The drill lasts for 24 hours from rescue to recovery and when done they'll scrub it and judge what went well and what needs to go better.
The CFD drill has been in planning for a while and has nothing to do with the recent bombing in Boston. The drill tests the City of Chicago's and suburbs' collaborative capabilities in the event of a tornado disaster.