Vicente Carrillo Leyva, a suspected deputy of the Juarez drug cartel, was arrested in Mexico City, El Universal reported Thursday.
The arrest of Leyva follows President Felipe Calderon's decision to increase the Mexican army's role in fighting drug traffickers.
Calderon has deployed about 45,000 troops -- nearly 50 percent of Mexico's combat-ready military personnel, along the U.S. border and throughout the country to deal with the drug cartels -- described by officials as a widening narco-insurgency, The Washington Post reports.
Meanwhile, retired army officers are taking command of local police forces and the military supplies civilian authorities with automatic weapons and grenades.
Mexico's four major drug states average a total of 12 killings a day, characterized by ambushes, gun battles and decapitated bodies left by the roadside.