Shops are closed and streets are deserted in Culiacan, Sinaloa, while smoke can be seen rising in the distance after intense gunfire rocked the cartel heartland in northwestern Mexico. A security source who did not want to be named told AFP that violence had broken out after an operation to capture Ovidio Guzman -- son of jailed drug kingpin Joaquin "El Chapo" Guzman -- but did not confirm reports by Milenio TV and other media that he had been captured. IMAGES