A months-long federal investigation has led to the discovery of a sophisticated cross-border tunnel allegedly used to move more than $45 million worth of cocaine from Mexico into the United States , resulting in charges against four individuals accused of participating in the operation. According to federal prosecutors, investigators with Homeland Security Investigations' Tunnel Task Force began monitoring a business known as Buy 4 Less in Otay Mesa, California, in late 2025 after observing activity that appeared inconsistent with a typical retail operation . Authorities said the store, located near the Otay Mesa Port of Entry, attracted little customer traffic despite a steady stream of workers and unusual movements in and out of the property. Investigators alleged that employees frequently transported large amounts of suitcases between the store and Mexico, raising suspicions that the location was serving as a front for a larger smuggling operation.…