In the heartland of Mexico’s Sinaloa cartel, the old ways have changed and violence rages The Associated PressA Cartel Double-Cross Turns a Mexican State Into a War Zone The New York TimesNarco Violence Leaves 200 Dead in Mexico’s Sinaloa in Grim Month BloombergDrug cartel cases in Chicago play disturbing role in surge of Mexico murders after both of El Chapo's sons arrested ABC7 ChicagoThe Take: El Chapo’s sons clash with rival cartel in Sinaloa showdown Al Jazeera English