TUCSON, Ariz. — Hiking through rough Arizona desert terrain a few miles north of the Mexican border recently with a group of armed DEA agents, we were approached by a lone U.S. Border Patrol agent. He warned we should be careful up ahead, because two people believed to be spotters for a Mexican drug cartel had just been seen running down a ridge to elude U.S. authorities.
By now, agents told us, the men were probably hunkered down in a cave or crevice to wait out the patrol. But just to be safe, the DEA agents spread out to cover more ground as they moved forward again, watching closely for the suspected Mexican surveillance team likely sent by drug traffickers to spy on American law enforcement officials on their own soil.
Making our way slowly to the rugged hilltops about a mile away, we came across several caves carved out of the rock by wind and rain. On the floor of one of them, we saw clear evidence that a surveillance team had been camping out. Two blankets were spread out next to a pair of shoes. Nearby were boxes of food, tarps, water jugs, toothpaste and a portable stove, on top of which was a pan with fresh cooking oil still in it.
Agents also found radio chargers and car batteries used to power communications gear. They told NBC producer-photographer Al Henkel and me that Mexican surveillance teams will work in these mountains for 30 to 60 days at a time.
“They locate themselves up on these ridgelines, up in caves, hidey holes, ‘spider holes’ we call them,” said DEA agent Todd Scott. He and the agents wondered if this particular “spider hole” was home to the two men just seen running away.
Estimated 200 to 300 drug scouts
Federal drug agents say Mexican cartel surveillance teams have set up observation posts on most of the mountain-tops in the Arizona west desert area, from the Mexican border to Phoenix more than 100 miles north. Most of that land sits inside the vast Tohono O'odham Indian reservation, which is the size of Connecticut, but is sparsely populated by only about 20,000 residents.
Officials say in recent years they have seen a dramatic rise in drug smuggling cases on Tohona O'odham land, attributing it to law enforcement crackdowns in others areas of the border, which have forced Mexican smugglers to increase their activities in the remote tribal lands that border Mexico.
“Before we used to see it maybe once or twice a week, but now we see it almost every day,” said Detective Charles May, of the Tohono O'odham Nation Police Department.
In the last few years, officials have seized hundreds of tons of marijuana there, along with a smattering of other illicit drugs, and have seen a rise in related crimes.
“All of this contraband is going right through where their villages, where their homes are,” said Lt. Michael Ford, also with the Tohono O'odham police. “People are concerned about where their kids are. They're concerned about the areas where they go to do traditional hunting or traditional gathering.”
Supporting the smugglers who cross the barren desert on foot or in vehicles, DEA agents said, is a small army of Mexican spotters hired by the cartels to climb the mountains, watch out for police and help coordinate illegal drug shipments.
“Typically these are low-level members of the Sinaloa cartel, the Mexican cartel, and we estimate at any given time there are about two or three hundred scouts working in these positions,” said Scott, the DEA agent. “With night-vision goggles, binoculars and things like that, the scouts check for Border Patrol presence, DEA presence, any law enforcement and they help guide and coordinate the smugglers on the ground.”
To speak with each other, and with the smugglers below, agents said, the spotters use sophisticated radios with rolling encryption, the sort used by military organizations. They also use radio repeaters and set up solar panels to charge the equipment.
“Basically, their job is to observe and report, as any other spy or military spotter,” said another DEA Agent Todd Smith.
As the smugglers move north into the United States, the surveillance teams in the mountains act almost like air-traffic controllers, handing off or contacting the traffickers as they leave or enter the spotters' area of control. “It's almost like a military operation,” said Smith. “Person to person all the way from the international boundary all the way up into the Phoenix area.”
Nighttime smuggling groups
Federal agents complain that the mountainous terrain in the Arizona desert is extremely difficult to control and at times appears wide open to smugglers. There is a grim joke among drug agents that someone could “smuggle a battleship” through the area without getting caught.
For most of the 75-mile-long border crossing through the Tohona O'odham Nation there is only a low-lying wooden fence separating Mexico from the United States. On the Mexican side of the border, staging areas for smugglers of drugs and migrants appear right along the fence.
“At nighttime, that's when everything moves,” said Lt. Ford. “You can hear people moving around, you can hear people talking, you can hear people walking.”
The smugglers often use heavily-camouflaged vehicles with all the inside lights taped over to avoid being seen at night. When spotters in the mountains give the all-clear signal to move north, the traffickers will sometimes drive right across the desert, or will set out on foot carrying drugs.
“A vehicle may have anywhere from 1,500 to 2,000 pounds in it and then you may have a human train of smugglers, 10 or 15 people each with a 40-to-60 pound pack on their back,” said Scott, the DEA agent.
In a large indictment announced in Tucson Thursday, law enforcement officials accuse 46 defendants, nearly half of them Tohono O'odham members, of helping the Mexican traffickers smuggle drugs through the reservation and then into Tucson and Phoenix.
They are alleged to have served as drivers, stash-house operators and suppliers providing food and water for the mountain-top spotters. Most of those charged were arrested in a sweep involving nearly 200 officers and led on the reservation by Tohono O'odham police.
Miles inside the United States
On top of a desert hilltop, near one of the spotter caves, a U.S. Border Patrol truck can be seen far below making its way along a dirt road. “You've got a clear line of sight all the way here to the roads that they coordinate the smuggling loads on,” said Scott.
In the distance, the intersection of two highways can be seen. On a clear day, a person standing here can see all the way south to the Mexican border and a long way north toward Phoenix. “You could see 10 miles from up here," said agent Smith, explaining the reason it's so hard to catch the Mexican spotters is that anyone approaching this area can easily be seen miles before they arrive.
The trash left behind by the spotter teams is testament to the spartan life endured by the men who spend days and nights here in desert heat and freezing cold.
“You have an interesting marriage of low-tech and high-tech. You have guys who live up here in these caves; we've seen them scratch calendars into the rocks to indicate how long they've been up here…with sophisticated radio equipment, transmitters, night vision equipment, all of which they utilize to help coordinate the loads moving down across this lower valley here,” said Scott.
And a point made repeatedly by the agents on patrol is that the elusive spotters who serve as the eyes and ears for a notorious Mexican drug cartel are operating miles inside the United States.
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