Cops on both sides of the US-Mexico border are investigating a sprawling underground passage uncovered in the Tijuana area that is believed to extend toward the US. The tunnel was found Saturday in the Nueva Tijuana neighborhood during a raid carried out by Mexican federal authorities with support from the Mexican Navy, according to Mexico’s Attorney General’s Office. The underground route was uncovered after authorities executed a search warrant at a property in eastern Tijuana. During the operation, officers seized a variety of items, including ammunition, cell phones, bank cards, a digital video recorder and dozens of doses of methamphetamine....