Cartels will stop at nothing to get drugs into America. The tunnels they dig under the southern border with pickaxes and shovels can sometimes stretch for miles. Laborers are often coerced at gunpoint or forcibly addicted to drugs. Some are even killed after the job is done. Enter the "Tunnel Rats"—an elite border patrol team that risks their lives to find and seal off these dangerous channels. In this special report, Epoch Times photojournalist John Fredericks meets the Tunnel Rats and tours a narco-tunnel in San Diego's Otay Mesa exclave.