Sadly there isn't one good site running with this story so I am not sure how we get the facts in the case. It seems the one problem standing in the way of getting the facts is the TSA itself; an agency whose screeners may soon be armed
Armed screeners? That's ridiculous. I don't hear too many stories of shoot outs at the airport. The last thing we need is to turn TSA screeners into a police force. Customs agents are often armed, but they are trained law enforcement as opposed to the misfits making $10 per how searching for smuggled barbecue sauce in a carry on.
Perhaps because they're security conscious zones and often have heavily armed officers present?