'Our agents are relentless': Feds shut down cross-border tunnel used by Mexican cartels for smuggling into US

U.S. and Mexican law enforcement worked together to locate and shut down a man-made cross-border tunnel used by cartels to smuggle cargo into the U.S. across the southern border -- complete with lighting and ventilation.

Border Patrol in El Paso, Texas, discovered the tunnel on Thursday. In a statement, Customs and Border Protection (CBP) said they discovered a man-made tunnel that breaches into the public storm drain.

The six-foot tall, four-foot wide tunnel was covered by a 36-by-36 inch entry hole.