"When I was in San Diego, there were some people from Sinaloa — we know it was the Sinaloa cartel — that rented a house and what they did is they built a tunnel in the bedroom, they took out tiles, built a tunnel, probably about 15 feet down, and then started excavate, and they hit a drainage system," Vigil said. They "came out underneath the international wall there separating Tijuana and San Diego, and they went to the drainage system and there was a huge parking lot there, a public parking area where people would park their cars and then they could just literally walk across the border."