SAN DIEGO (AP) — Smugglers are advertising jobs in Mexican newspapers for security guards, housecleaners and cashiers in a scheme to recruit the unemployed and underemployed to drive drug-laden vehicles into the United States. Now U.S. authorities are also buying space in classified advertising sections.U.S. Immigration and Customs and Enforcement is warning job applicants in two Tijuana newspapers that they may be unwitting pawns for drug cartels. The ads began Sunday are scheduled to run for one month.ICE says there have been 39 arrests at San Diego's two border crossings tied to newspaper ads for seemingly legitimate jobs since February 2011. They have resulted in a tiny fraction of total seizures along the entire border but enough to convince authorities that smugglers are increasingly turning to the technique.