MEXICO CITY - Mexico may turn to international courts in an effort to block a new Arizona law limiting services to illegal immigrants, Foreign Secretary Luis Ernesto Derbez said Wednesday. He said in a radio interview that Mexico might take such a step after it has exhausted all possibilities under U.S. law to halt Proposition 200. "We are seeking all the legal opportunities that exist, first using the legal capacities of the United States itself and ... if that does not work, bringing it to international tribunals," Derbez said. advertisement He did not specify to which international bodies Mexico could...