How smugglers build and use tunnels along the US-Mexico border NOGALES, Ariz. (AP) — As border security has tightened, drug cartels have turned to tunneling beneath the ground to avoid...
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How tunnels are built, used along US-Mexico border
How smugglers build and use tunnels along the US-Mexico border NOGALES, Ariz. (AP) — As border security has tightened, drug cartels have turned to tunneling beneath the ground to avoid...