Smugglers have a “very sophisticated” operation for trafficking into the United States through a route that leads, of all places, through the headquarters of U.S. Army intelligence in Arizona.

“That smuggling operation going through there is very, very sophisticated,” former U.S. Border Patrol supervisor Dave Stoddard told KVOA, a local news outlet in Tucson. “They’ve been getting by with it for years. They know the formula. They know the routine.”