He grew up poor in Nogales, Mexico, just across the border from Arizona. His dad died when he was a teen, his mother worked as a cook. He couldn't afford the things he wanted. There weren't many jobs for a guy like Pancho, as he calls himself.

But there was a steady gig that paid $2,000 a week — smuggling marijuana across the U.S.-Mexico border — and Pancho took it. He's 29 now, a father of five, and he says he works long hours to support his family, "so that they won't be in need." It's a risky life, but he's done it for 12 years, and he doesn't think anything President Donald Trump does about a border wall will stop the illegal narcotics trade.

"No matter what you do here, we can still get through," said Pancho, while sitting in the dim light of an abandoned tenement just a few minutes south of the border. It was cold and damp, and he sat hunched in a chair in a musty room with a dirty old mattress and newspapers scattered across the floor. The fence along the border used to be shorter, he recalled. It's higher now, but that's no impediment.

Smugglers always seem to find a way around such obstacles — over, under or around. US law enforcement agents know this.

"Drugs will come in through every direction," said Santa Cruz County Sheriff Tony Estrada in Nogales, Ariz., located just across the border. "They'll throw the drugs over the fence. They'll push them through." That or they will tunnel beneath or send people deep into the mountains, where the fence is less obtrusive.

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"These cartels, they're a 24/7 business, thinking of ways to bring drugs across," Estrada continued. "They'll do it through the ports of entry, the Mariposa commercial port. You know, they'll get a ton, two tons of marijuana come in on some of those trailers."

The drug smuggling is unrelenting.

"Illegal immigration pales compared to the drug problem that we have," Estrada said. He started in law enforcement 50 years ago. Back then, "they told me it was going to take three generations to wean people off of drugs. We're worse off than we were then, and it's not getting any better."

On a typical day, Customs and Border Protection (CBP) nabs an average of 7,910 pounds of drugs. Last year, U.S. border agents seized 5,473 pounds of cocaine, 8,224 pounds of methamphetamine, 9,062 ounces of heroin and 1.29 million pounds of marijuana.

Pancho says he has been smuggling for 12 years and always finds a way across the US-Mexico border. Credit: Karen Coates

CBP employs 60,000 people to enforce the law along the country's borders, using everything from dogs and blimps to large-scale X-rays and Gamma-ray imaging systems and remote video surveillance systems. According to Ralph DeSio, a CBP public affairs officer in San Diego, border security operations involve the use of thermal imaging devices for night vision, aircraft equipped "with radar and other technologies," and "a specialized radar for slow-moving signatures."

In addition to all of this, Immigration and Customs Enforcement deploys special "tunnel task forces" to combat underground activity. Yet the smugglers still get through.

Regarding Trump's proposed wall, DeSio said, "we cannot speculate on that in any way." But he pointed out that San Diego currently has 46 miles of primary fence and about 13 miles of secondary fence, noting that because "tunnels go very deep and long distances, they still pose a threat."

Estrada remembers when the first drug tunnel was discovered in Nogales in 1995, "two blocks away from the Dennis DeConcini Port of Entry at an old abandoned church right next to what is now the Burger King." That was around the same time federal authorities built a bigger fence, which he refers to as "a wall." Since then, at least 110 more tunnels have been found.

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"Why? Because it's practical — we're back-to-back," he said, referring to the fact that the American Nogales and the Mexican Nogales are virtually contiguous, despite the border. There's no river to separate the towns, "no buffer zone."

In fact, the decades-old drainage system that underlies Nogales on the Mexican side offers a big, dark causeway leading straight to the United States. You can enter through the street, slosh through the runoff from recent rains wearing a headlamp, and follow the tunnel to a floodlit vestibule between two gates, which at that point is all that separates the U.S. from Mexico.

Immigrants, vagrants, laborers, and criminals have all used these tunnels for sanctuary and passage. When it rains hard, the force of water shoves the gates open, washing debris and sometimes people through to the other side.

"The flood water comes in and takes them by surprise after a rain, and that's how they drown," explained a Nogales law enforcement agent named Gilberto. Officers on either side of the border regularly patrol the tunnels for suspicious activity. When motion sensors detect movement, U.S. Border Patrol notifies the Mexican authorities.

Tunnels beneath Nogales, Mexico, lead straight into Nogales, Ariz. Credit: Karen Coates

"We do rounds together," said Roberto Contreras of the Sonora Fire Department. "But we make sure to identify each other so we don't shoot each other."

Pancho doesn't smuggle his goods underground — he goes over, through the desert. The journey he describes involves a group of eight, including a communications director to guide the group and two people to carry food, with the rest working as "mules" hauling handmade backpacks: 20- to 40-pound squares of drugs covered in tape and wrapped in blankets.

It takes "about two days walking in Mexican land," he said. On the third morning, the group enters U.S. soil, where lookouts watch for them. They communicate by radio, noting when the route is clear and when it isn't. Sometimes the smugglers stay high in the mountains until it's safe to move. After five or so more days of walking, the group reaches a ranch and eventually a road, where two vehicles arrive to fetch the group and its valuable cargo. Then it's on to Tucson, where they arrive at an apartment, shower, retrieve their pay, and are soon on their way back home across the border.

Video footage from private ranch lands in Arizona verify what Pancho describes: men lugging rectangular backpacks, wearing carpet booties on their feet that leave no tracks. Smugglers scramble over the border fence. They fling bundles with catapults. Lookouts stand watch on hilltops. The groups quietly hike north, day after day.

"Things are becoming more complicated," Pancho conceded. "There is a lot of surveillance… more vigilance, more cameras."

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This has forced the smugglers to take longer routes through rugged terrain.

"There are areas here in Santa Cruz County that you can't get into," Sheriff Estrada said. "You have to be dropped down by helicopter." And that's exactly where smugglers go. "They will travel to those areas for days in order to get their product across. So it's always going to be a challenge."

In the 1990s, when the wall went up in Nogales and the tunnels went under, local authorities started getting more calls for help in the hinterlands.

"People were dying out there — because of the weather, pre-existing conditions, too cold, too hot," Estrada said. "Some of them obviously were being victimized. Women were being assaulted, sexually assaulted. People were dying."

When someone dies in Santa Cruz County, "we are responsible for the recovery and the proper identification," explained Sheriff's Deputy Sergeant Omar Rodriguez. He patrols the desolate areas near the border through Operation Stonegarden, a federal program that partners local law enforcement agencies with the Department of Homeland Security.

Sheriff's Deputy Sergeant Omar Rodriguez says there isn't enough law enforcement to stop smugglers. Credit: Karen Coates

"This is the Coronado National Forest," he said, indicating a stretch of land. "You have a few ranches in the area, open cattle range," with steep mountains to the east and not much else.

But 10 to 15 times a year, the department is called to retrieve human remains.

"And that's only reported cases. Who knows how many are out there that no one has found," Rodriguez added. "It's unfortunate." About 20 percent of the time, he estimates, identification is never made. "Most of the people we've found as deceased are probably Mexican."

Rodriguez doesn't think a barrier will keep people from crossing the border.

"They continue coming and they climb the fence like it was nothing," he said. "We don't have the manpower to stop everything."

Meanwhile, the urge to sneak across remains strong in Mexico and in much of Central America, with scores of migrants coming up through the south of Mexico to make their way to the U.S.

"Nowadays it's really kids under 20 who are taking over the business," Pancho observed, just as he joined the trade at the age of 17. "They're all looking for the easiest way to get a gig because it's very difficult to make a living here."

But at 29, Pancho is ready to retire. "I want to be another person," he sighed. "I don't want to be doing this anymore."

He dreams of settling in New York for a while, working like anyone else, and returning home after saving money to start his own business in Mexico. He's thankful for the job he's had — "having the money in your hands, it's worth it" — but he does have one regret.

"A person died in the desert," he said. "It was a person who worked for us. A heart attack… it was extremely cold. He could not endure." The man was 32 or 33.

His remains "never appeared and will never appear," Pancho went on. "We couldn't carry the corpse, and so it got lost there. Every time we pass by, we light a candle."

A small flame for the bones of an unidentified man in the desert.

The International Women's Media Foundation supported the reporting for this story. The author is a senior fellow with the Schuster Institute for Investigative Journalism at Brandeis University.

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