When Mexican President Felipe Calderón took office in December 2006, he announced a crackdown on cartels by the Mexican military to stem the increasing violence. After four years, the additional efforts had not slowed the flow of drugs or the killings tied to the drug war. Of the 53,000 arrests made as of 2010, only 1,000 involved associates of the Sinaloa Cartel, which led to suspicions that Calderón was intentionally allowing Sinaloa to win the drug war, a charge Calderón denied in advertisements in Mexican newspapers, pointing to his administration's killing of top Sinaloa deputy "Nacho" Coronel as evidence. Sinaloa's rival cartels saw their leaders killed and syndicates dismantled by the crackdown, but the Sinaloa gang was relatively unaffected and took over the rival gangs' territories, including the coveted Ciudad Juárez-El Paso corridor, in the wake of the power shifts.