Under a scorching sun in the harsh desert along Highway 9 in southern New Mexico, Border Patrol agents Rito Jara and Juan Treviso are quickly on the move, scouring the hard ground, trying to pick up footprints from suspected drug smugglers or immigrants who entered the U.S. illegally from Mexico.

The agents discovered the footprints next to a cattle fence while on routine patrol early in the morning about three miles north of the U.S.-Mexican border. Finding more prints across the highway, they determined that two men passed by here around midnight, eight hours earlier. It appeared they were walking north across the barren scrubland toward either the town of Deming, New Mexico, or U.S. Highway 10, where they could be picked up and spirited away.

Joining the search, Border Patrol Field Operations Supervisor James Acosta said it was possible the men had already reached the Cedar Mountain Range, many miles ahead, and were now hunkered down to avoid daylight search parties and the searing heat. One potential hideout, Acosta suggested, was a notorious mountain pass known locally as Doper’s Gap, because of all the Mexican traffickers who have already passed though there carrying burlap knapsacks filled with illegal drugs bound for U.S. street corners. As of this writing, the two men who left their tracks along the highway were still being sought.

Three years ago, smuggling and illegal immigration were so out of control in southern New Mexico that the governor declared a state of emergency and called in the National Guard to assist the U.S. Border Patrol. “We had several narcotics organizations that were exploiting that particular area,” said Acosta.

Agents said law enforcement efforts to slow illegal border crossings in neighboring Texas and Arizona had the unintended effect of forcing thousands of Mexican immigrants and smugglers to change routes and brave the harsh conditions in New Mexico’s desert, where in many places there was nothing more than a wire fence separating the two countries.

It was not uncommon then for the Border Patrol to report hundreds of apprehensions a night and for ranchers to complain of widespread thefts and break-ins as illegal immigrants trekked north into the United States.

In a further attempt to seal the border and restore order, the Border Patrol this year opened Camp Ramsey, a permanent forward operation base, or FOB, in the middle of the desert. It is 26 miles west of Columbus, New Mexico, the nearest town, and 60 miles from Deming, where the closest Border Patrol station is located.

Sixteen agents are assigned to the FOB on a rotating basis and work twelve-hour shifts, day and night. “We need them close to the border, which is going to reduce the time to respond,” explained Acosta, who helped open the facility. Camp Ramsey has dorm rooms, showers, television and a dining facility for the agents, along with holding cells and processing facilities for detainees.

Every day, at noon and at midnight, a fresh team of agents heads out on the desert to begin a new search. Their high-tech arsenal includes seismic sensors, which detect people walking across the desert, heat-seeking cameras, lasers and night vision goggles, which are used to pinpoint immigrants crossing the border under cover of darkness.

Even on the black and white camera monitors used at night, agents can easily determine when the images on the screen are from drug traffickers. “Usually you can tell when it’s dope, because it’s a bigger bag that they carry and they’re pretty hunched over,” said Francisco Guerrero, a Border Patrol agent manning a mobile camera site.

Of equal importance, though, and used widely by all the agents in the desert, is a low-technology skill known as “sign cutting,” a tracking method perfected centuries ago by Native Americans hunting for food.

“We keep our eyes to the ground, we try to pick up any disturbances, whether it’s brush, whether it’s a footprint on the ground, a turned over rock, just anything,” said Acosta. Sign cutting helps agents determine whether a person is crossing the desert, how many others are with him and how long ago they passed by. All that, agents say, can be seen in the dust, rocks, grass, bushes, anthills and prairie dog mounds that cover the landscape here.

“Agents do it everyday, every single day agents are finding people, finding narcotics, finding illegal crossers off one footprint,” said Acosta while standing near a dry wash, which is a known route for smugglers on foot. “This is all drug trafficking right here, every bit of it,” he said. “The fact it sits just a little bit lower than the surrounding area gives them a little bit more cover.”