In Mexico, at least 30 people have died after drug-related violent crime rocked the cities of Monterrey and Guadalajara, and the northern state of Chihuahua. The police said yesterday the attacks were the latest deadly violence gripping Mexico's war on drugs, as the country's various criminal cartels struggle over turf and attempts of the police and soldiers to crush them. More than 34,600 people have died in drug trafficking related violence since December 2006.