Border tunnels left unfilled on Mexican side pose security risk, officials say - LA Times

Border tunnels left unfilled on Mexican side pose security risk, officials say - LA Times: Mexican drug cartels have burrowed dozens of tunnels in the last decade, outfitted them with rail and cart systems to whisk drugs under the U.S. border and, after being discovered by authorities, abandoned them.

But some of the illicit passageways live on.

At least six previously discovered border tunnels have been reactivated by Mexican trafficking groups in recent years, exposing a recurring large-scale smuggling threat, according to U.S. and Mexican law enforcement officials.

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