Agents found the tunnel, which opened into a storm drain on the Texas side, in late June after hearing suspicious noises in the area near the Bridge of the Americas, the El Paso Times reported. It was 130 feet long and unventilated but big enough at about 2 feet high and 2 feet wide for drug smugglers and other illicit border-crossers to use, officials said Tuesday.
About 200 pounds of marijuana and a Mexican teenage boy were in the tunnel, said Demetrio Guerra, supervising agent with the Border Patrol.
A contractor used steel plates and concrete in September to render the tunnel impassible, the Times reported.
"It's been completely sealed off -- permanently sealed off," Guerra said.
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