I thought on of these happened near Cicero, IL some time ago, but it was at a Brown’s Chicken (almost indistinguishable from Church’s, both dry and flavorless). That one was much worse.
http://articles.chicagotribune.com/2013-01-08/news/chi-browns-chicken-killings-anniversary_1_brown-s-chicken-richard-and-lynn-ehlenfeldt-chicken-killings
My mistake. It was indeed a Brown’s.