NOGALES, Mexico — Father Ricardo Machuca strides back and forth between six long, metal picnic tables packed with men and women as volunteers pass out plates piled high with corn, beans, rice and pork rinds. Clutching a microphone and wearing jeans, a white tunic, sandals and a messenger bag, Machuca looks more like a bohemian motivational speaker than a Jesuit priest.

Don’t accept offers from strangers who want to help you cross, he warns his audience in Spanish as they quietly dig into their meals. Crossing with coyotes is human trafficking and it’s “un delito federal,” he says. A federal offense.

In recent years, warnings about who to avoid on the streets of Nogales have become a key part of Machuca’s advice to those who pass through the binational Kino Border Initiative’s migrant outreach center. Better known as the Comedor, meaning “soup kitchen” in Spanish, the center has been offering hot meals, first aid, clean clothing, and spiritual guidance to migrants since 2009. Someone offering to help wire money could rob you, Machuca tells the migrants. Or a stranger willing to let you use their cellphone to call your family might save their number and use it to extort them later.

“The vulnerability is very high here on the border,” Father Sean Carroll, Machuca's American counterpart, tells me as an assembly line of volunteers rushes hot plates from the kitchen to the tables. “They want to contract the migrants to try to cross again.”

Carroll is referring to Mexican drugs cartels, along with the smugglers hired by the cartels to recruit desperate migrants looking for a way back into the United States. Over the past decade, after long existing side by side with coyotes, the cartels decided to get in on the action. Now, they've turning what was once a relatively informal and somewhat familial underground operation into a highly sophisticated human trafficking network.

While the journey north was always treacherous and costly, in the hands of the cartels it has become deadlier than ever. The entire border, and the routes leading up to it, are controlled by some combination of the Los Zetas, Sinaloa and Knights of Templar cartels, along with a few smaller groups—making it impossible to cross without their permission. And their permission will cost you. Where migrants may have once paid a single person from their hometown $300 to $500 to guide them across, the initial going rate to cross the cartel-occupied border can range between $3,000 and $6,000 per person, the price varying depending on the age, gender, and origin of the migrant. Most people can’t afford that much up front, so family members in the States will often wire money to the smugglers, or pay in installments along the way.

Under the cartel-run migration model, migrants typically make arrangements to cross from their hometowns and are told to find their own way to a certain point where they will meet the coyote. The city of Altar, for example, about 112 miles from Nogales in the Mexican state of Sonora, is a popular launching point for border crossers, and as such, it has become a center of immigration commerce. Here, smugglers often tell migrants to wait for days before they cross, during which time they are nickel-and-dimed into buying stealth desert-crossing gear—camouflage backpacks, black water bottles, and carpet booties—from vendors who set up shop around town.

For those coming from Central America, just getting to a meeting place like Altar often means riding buses or atop freight trains from southern Mexico where they may be subjected to robbery, beatings, and getting thrown off the train by cartel lackeys. Those who make it will continue to encounter crippling fees at practically every leg of their journey to the border. Refusal or inability to pay may result in migrants being forced to carry backpacks filled with marijuana, getting kidnapped in order to extort money from their families, or being murdered on the spot. Last year, Zetas leader Miguel Angel Trevino Morales was captured by Mexican Marines and charged with ordering the kidnapping and murder of 265 migrants. For female migrants, there is always a good chance they could be raped along the way, either by their guide or one of the stray predators who stalk the desert.

It’s almost impossible to separate the cartels’ migration takeover from the security crackdown on the U.S.-Mexico border. In the 13 years since U.S. Border Patrol became a part of the post-9/11 Department of Homeland Security and adopted the mission of keeping terrorists out of the country, the Southwest border has been transformed into a militarized zone, with nearly 700 miles of varying degrees of steel fencing, 21,000 Border Patrol agents, security cameras and ground sensors, with more high-tech surveillance on the way. Some combination of this beefed-up security, a George W. Bush-era policy of jailing and formally deporting all illegal border crossers, plus the U.S.’ weakened housing and job markets, brought the net flow of migration from Mexico to a standstill in 2011. While traffic over the border has slowed, those still crossing have been funnelled into the roughest corners of the desert, where human predators are only part of the danger.

To avoid areas where Border Patrol agents are most highly concentrated, migrants must take longer routes through Mexico, often walking for days through the blistering heat and unpaved and often mountainous desert terrain, dodging rattlesnakes, yellow jackets and cacti, before they even reach the international line. It’s physically impossible to carry the amount of water needed for more than a few days in the desert.

To coyotes getting paid for each person who successfully makes it over, it’s not worth the risk of stalling the whole group to stop and care for someone who is hurt or sick. More often than not, those who can’t keep up will be left to die in the desert. Even as the number of illegal crossers apprehended at the border has reached all-time lows, more people are dying than ever. According to a report by the human-rights group the Washington Office on Latin America, 463 migrants died in fiscal year 2012. The last time that there were more deaths was in 2005, when 492 migrants died. But the pool of people crossing over was much larger—that year, Border Patrol apprehended three times as many people as in 2012.

Juanita Molina is the executive director of Border Action Network and Humane Borders, two Tucson, Arizona-based humanitarian groups that set up water tanks in the desert based on their maps of where the most deaths occur and advocate for humane treatment of migrants and border communities by Border Patrol. She argues that the criminalization of economic migration has backed an already vulnerable group of people into a corner, with the cartels capitalizing on the situation.

"As a society, we feed the danger by forcing all of these people into the shadows," Molina told me at her office in Tucson. She speculates that limiting the ability to cross the border to the most dangerous areas was part of the Border Patrol strategy to deter people from crossing.

“Or maybe they didn’t care that people were dying, that there is a certain amount of collateral damage that comes with enforcement,” she says. “It’s hard to know.”

What Molina does know, from mapping desert deaths for the past 12 years, is that people are dying closer to the international line and farther from the roads in town. “The dynamic of pushing people further into these wilderness areas is almost like putting out meat for the wolves,” she says.

Central American migrants are naturally more vulnerable to cartel manipulation and violence on the journey north than native Mexicans. But the cartels may actually be responsible for the recent influx of Central Americans attempting to cross the Southwest border and, specifically, the surge in unaccompanied minors coming from the region.

In 2011, the World Bank declared narcotics trafficking to be one of the greatest threats to development in Central America. After Mexican President Felipe Calderon launched a military crackdown on drug traffickers within his country in 2006, Mexico’s most powerful cartels—Los Zetas, Sinaloa and others—started to spread south, recruiting local gangs to join their operation and terrorizing Guatemalan, Honduran, and Salvadoran cities with the same indiscriminate violence that once made Ciudad Juarez the world’s murder capital. Whereas three political parties plus institutions like the Catholic Church and the business community have prevented Mexico from completely crumbling under the cartel chaos, Central America’s historically fragile economy and easily corruptible political, judicial and military systems are much less poised to withstand the weight of the wealthy and heavily-armed drug cartels. Peace accords to end Guatemala’s civil war in 1996, for example, cut the country’s army by two-thirds, leaving a major opening for organized crime. As of 2011, Guatemala’s murder rate was double that of Mexico. And while that rate technically dropped during the past three years, the U.S. Department of State’s Bureau of Diplomatic Security noted in its 2013 Crime and Safety Report that the commonly cited statistics provided by Guatemala’s Policia Nacional Civil undersell the homicide situation, as they do not include murders in which the victim didn’t die right at the scene of the crime.

“Guatemala’s worrisome murder rate appears driven by four key factors: an increase in narco-trafficking activity, growing gang-related violence, a heavily armed population (upwards of 60 percent possess a firearm), and a police/judicial system that remains either unable or unwilling (or both) to hold most criminals accountable,” read the report. “Well-armed criminals know there is little chance they will be caught or punished.”

Meanwhile, Honduras and El Salvador have maintained the world’s highest and second-highest homicide rates since the mid-1990s.

By making these countries so dangerous and virtually unlivable for their poorest citizens, the cartels have effectively created an incentive for people to flee, providing themselves with more clientele for their human smuggling business to supplant the hole left by the drop in Mexican migrants.

The cartels are also driving the current border-children crisis in the U.S. Since last October, 52,000 unaccompanied minors were apprehended by Border Patrol. House Speaker John Boehner and other Republicans have blamed local news coverage in Central American countries of Obama's pathway to citizenship for the massive influx of kids. But as The Huffington Post discovered by scouring Central American news reports, regional media has accurately covered DACA and the proposed Comprehensive Immigration Reform and regularly depicts President Obama as tough on immigration.

In reality, it’s more likely a loophole in the George W. Bush-era policy of expeditiously charging, imprisoning, and deporting adult illegal border crossers that is drawing children in droves. According to this policy, while Mexican minors can be sent back over the border immediately, minors from other countries must be held in Customs and Border Protection’s custody for a maximum of 72 hours before they are turned over to the Department of Health and Human Services’ Office of Refugee Resettlement. ORR houses the minors in shelters while searching for U.S.-based relatives with whom they can stay during their deportation proceedings. As of March 2014, there were 366,758 pending deportation cases in U.S. immigration courts. That backlog means even just receiving a court date could take years, by which time the minor could make the case that they are better off with their extended family in the States. Or they could just not show up to court and choose to live under the radar like the 11 million other undocumented immigrants in the United States. No doubt the criminals interested in recruiting border crosses have emphasized to families that kids face better odds in the U.S.—and so the children keep on coming.

Last week the Obama administration publicized plans to open more facilities to detain children and families, and to reassign immigration officers and judges to speed up deportation proceedings. During a visit with senior leaders from Guatemala, El Salvador and Honduras in Guatemala on Friday, Vice President Joe Biden announced the U.S. would be dedicating $225 million to the Central American countries to better prosecute gang members, cut down on gang recruitment with youth outreach programs, and help reintegrate deportees.

On the opposite side of the border in Nogales, Arizona Border Patrol spokesman Peter Bidegain is pointing at a two-story yellow brick house just across the border fence. “This yellow building here, it’s operated by the one of the cartels as a scouting facility," he says. Nearby, a yellow Caterpillar excavator sits idle next to an opening that once led into a cross-border tunnel. “You can see guys on the porch sometimes with binoculars. They work in shifts just like we do.”

Bidegain describes a common cat-and-mouse game played by smugglers and the Border Patrol agents in which migrants are led over the fence on a ladder, prompting the agents to go after the migrants and allowing drug smugglers to sneak by. Vast scouting networks using cellphone or radio transmissions, powered by solar panel battery chargers in the mountains, allow lookouts on both sides of the border to study Border Patrol agents’ every move, waiting for the perfect time to pounce. With Border Patrol and Mexican police stacked on either side of the 15-foot-high steel wall, drugs stuffed in the sides of cars or fake fruit in the back of trucks or even on the back of a single person have a better chance of making it through Nogales than a group of migrants.

“A lot of times the people who are being smuggled here are just being used as bait,” he says.

Some suspect the recent inundation of unaccompanied minors at the border is part of a strategic move by the cartels to distract Border Patrol while they move drugs.

“We have grave concerns that dangerous cartel activity, including narcotics smuggling and human trafficking, will go unchecked because Border Patrol resources are stretched too thin,” Texas Attorney General Greg Abbott wrote in a letter to Department of Homeland Security Secretary Jeh Johnson this month, requesting $30 million for additional law enforcement. Recent U.S. Drug Enforcement Administration statistics back this theory. Total marijuana, cocaine, heroin and methamphetamine seizures between January 1 and June 14 of this year have dropped across all states that line the U.S.-Mexico border, but the decrease in Texas—the center of the surge in unaccompanied minors—has been bigger than the average, at 34 percent. The DEA and Border Patrol have said it’s too soon to tell whether the decrease in drug seizures is at all connected to the increase in underage crossers.

As policymakers debate how best to handle the current immigration crisis, the day-to-day game of Whack-A-Mole continues along the border. Border Patrol zeroes in on the highest trafficked areas and, in turn, smugglers change position.

“They will use what’s successful, so they’ll try anything,” Bidegain told me. “It just depends on the smuggling du jour.”