Homeland Security Investigations agents first began surveillance of a San Diego shop called Buy 4 Less, located near the Otay Mesa border crossing, in December 2025 after suspecting the store was being used to conceal a subterranean tunnel, according to a federal criminal complaint filed Monday. The agents observed activity that “did not appear to be consistent with a normal retail location,” the complaint said — the store had few customers, and men frequently entered and exited carrying empty-looking suitcases, sometimes walking them across the border into Mexico.
On May 29, agents saw the suspects gather in three vehicles and load a truck with deep freezers filled with packages. San Diego County sheriffs stopped the truck, and drug-sniffing dogs alerted on the packages. A search of the other two vehicles also yielded illicit drugs, bringing the total amount of cocaine seized to more than 2,250 pounds — just over one metric ton — the U.S. Attorney’s Office for the Southern District of California reported.
After the arrests, federal agents searched Buy 4 Less and discovered a 55-foot-deep vertical shaft equipped with a sophisticated hydraulic lift, leading to a tunnel that extended more than 1,000 feet toward the border. The passage, about 4.5 feet tall, was fitted with a rail-and-cart system, electric lighting, and ventilation. Investigators believe it continued roughly 800 feet beyond the border into Tijuana.
The four defendants include two Mexican nationals and two U.S. citizens, ranging in age from 18 to 32. All are charged with conspiracy to traffic drugs across the U.S.-Mexico border and face potential life sentences. Gregorio Epifanio Hernandez Lopez is also charged with constructing, financing, or using an unauthorized tunnel.
“This investigation and seizure represent a significant blow to the Jalisco New Generation Cartel,” Kevin Murphy, acting special agent in charge for HSI San Diego, said in a statement. “The discovery and dismantlement of this sophisticated cross-border tunnel, along with the seizure of more than a ton of cocaine, underscore the commitment and collaboration of Homeland Security Investigations and our Homeland Security Task Force partners.”
The tunnel is the first such cross-border passage discovered in southern California since 2022. According to the U.S. Attorney’s Office, authorities have found 99 tunnels along the border since 1993, of which 28 were classified as sophisticated.