A band of Mexican army deserters that smuggles illicit drugs into the United States across the southern Texas border has offered bounties of up to $50,000 for the assassination of U.S. Border Patrol agents and state and local police officers, U.S. law-enforcement authorities said. The gang, known as the "Zetas" or the "Z's," is suspected in nearly 90 deaths of rival gang members in the past two years as part of a violent drug war to control trafficking across the Mexico-Texas border. Members use their military training and stolen equipment, including high-powered weapons, to fight competing organizations.