U.S. Homeland Security Secretary Janet Napolitano said Thursday that more inspections of vehicles heading into Mexico and intensified intelligence gathering on the U.S. side of the border would be part of an effort by both countries to stop weapons trafficking into Mexico. “On the Mexican side, more uniform and routine collection of arms tracing done on a real-time basis” will be needed, Napolitano told the Associated Press as she flew to the weapons trafficking conference in Cuernavaca, south of Mexico City. Napolitano and U.S. Attorney General Eric Holder met privately with their Mexican counterparts—Interior Minister Fernando Gomez-Mont and Attorney General Eduardo Medina-Mora—as well as other officials from the two countries at the conference. The delegations discussed tougher penalties for violating both countries' gun laws as one way of fighting drug cartels blamed for horrific violence in northern Mexico that has started to spill over to the U.S. side of the border. Most of the weapons used in the Mexican drug war—which has killed more than 7,000 people in the past 15 months—are smuggled across the border from gun dealers in the United States.