Drug traffic picking up in Mexico-US tunnels

SAN DIEGO — Mexican drug cartels have burrowed dozens of tunnels in the past 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.

The breaches of border defenses, most recently in December, occur because Mexican authorities don’t fill the tunnels with concrete when they are found, saying they don’t have the funds.

Instead, only the tunnel openings are sealed. That lets traffickers simply dig a new entry point to access the tunnels leading to the U.S. border.

The security lapse is a boon for traffickers, experts say, saving them time and money and reducing their risk of being caught as they haul away dirt.

“The biggest threat is that it’s a huge open invitation for drug traffickers, and it’s definitely going to be taken advantage of,” said Michael Unzueta, a former special agent in charge of Immigration and Customs Enforcement in San Diego.

On the U.S. side, drug tunnels have been filled since 2007, after The Los Angeles Times reported that they were being left unfilled because of budget constraints at U.S. Customs and Border Protection.

Prompted by U.S. Sen. Dianne Feinstein (D-Calif.), who called the tunnels a “national security risk,” the agency has filled every large tunnel up to the border ever since, according to Department of Homeland Security officials.

U.S. authorities at the time expected traffickers to reactivate the tunnels, and some recommended the U.S. consider paying Mexico’s costs of filling the tunnels on its side.

But funding was never appropriated.