CHICAGO/MEXICO CITY (Reuters) -When Silverio Villegas Gonzalez was 12 minutes late for his shift at Tom & Jerry's Gyros, a diner on Chicago's northwest side, his manager knew something was wrong. Earlier that morning, Villegas Gonzalez, 38, had been fatally shot by a U.S. Immigration and Customs Enforcement agent shortly after dropping his children off at a school and daycare in the suburb of Franklin Park. Villegas Gonzalez was the Chicago crackdown's first casualty.