Sophisticated tunnel found across border

PHOENIX — An incomplete tunnel found stretching from Mexico to Arizona appears to be “the most sophisticated tunnel in U.S. history,” authorities said.

The tunnel, intended for smuggling, ran from a neighborhood in San Luis Río Colorado, Mexico, to San Luis, Arizona, where it stopped short of reaching the surface. It was built in an area that’s not conducive to tunnels because of the terrain, and it had a ventilation system, water lines, electrical wiring, a rail system and extensive reinforcement, federal officials say.

“What makes this one unique is that the terrain in Yuma is very hard … the sand is very loose, and most of them end up caving. So the fact that the material was very well-built and it had ventilation, it had water, it had a rail system with walls, roof, floor, electrical, makes this one a very unique type of tunnel,” said Angel Ortiz, assistant special agent in charge for Homeland Security Investigations in Yuma.

“This appears to be the most sophisticated tunnel in U.S. history, and certainly the most sophisticated I’ve seen in my career,” said Carl E. Landrum, acting chief patrol agent with the Border Patrol’s Yuma Sector.

Homeland Security Investigations started excavating around the tunnel in late July after someone reported a sinkhole near the border wall.

The tunnel measured 3 feet wide and 4 feet high.

Investigators don’t know what exactly the tunnel would have been used for, since it was incomplete. They also don’t know how long it had been there, because they don’t know what kind of equipment was used to build it.

If it was done by hand, it would be many months of construction to get as far as it did, Ortiz said.

But if the builders used heavy machinery it would “potentially a few months, not that long of a period,” Ortiz said.