Officers also eyeball each person to check for drugs or weapons. Some are obvious — like the man officers caught recently with 13 pounds of marijuana strapped to his body.

"He looked like the Michelin Man," Jimenez said. "Three, four pounds, maybe you can conceal it, but 13 pounds?"

Six years ago, Manuel Hernandez of Salt Lake City made a surreptitious dash to the United States to better his circumstances. He paid a human smuggler, known as "a coyote," $1,300 — borrowed from a friend — to drive him across the Mexican border. He was among 10 others crammed in a van that set out across the desert. He left a wife and two children at home in Veracruz.

"It wasn't hard because I wanted to be here so badly," he said through an interpreter.

Hernandez came to Utah looking to earn more than the paltry agricultural living he made in Mexico. He found a job at a food-processing plant where he worked for four years, sending money home to his family. He had to quit two years ago when he was diagnosed with kidney disease.

Later, his son came across the border in the same way his father did. Hernandez said his wife and daughter are still too scared to sneak into the United States.

A few blocks from the port of entry is the processing station for the U.S. Border Patrol in El Paso, Texas. Here a line of mostly young men in muddy boots and pants dirty up to the knees wait to be walked back across the bridge into Mexico. They've been caught sometime in the past 12 hours.

On the U.S. side of the border, a row of U.S. Border Patrol agents with a "hold the line" philosophy about border protection line the dirt roads. Powerful floodlights are stationed every 30 yards and are trained on the Rio Grande and the cottonwood trees that grow in its bed.

In the past 11 months, agents in the El Paso sector have caught 110,000 men, women and children crossing the border illegally.

That's 300 every day along the 180 miles of land where Mexico touches the boundary of El Paso, Texas, and parts of New Mexico.

Some days, agents catch mostly "day crossers" — roofers, gardeners, cement workers — who make their way into Texas or New Mexico to work.

"They go back every day," border patrol agent Jorge Martinez said. "They are just trying to earn a living."

Intense attention at this border checkpoint means some trying to cross move east or west and try to cross in much more dangerous terrain.

Nearby, in Arizona, 26 migrants died in the desert this summer trying to cross into the United States without adequate water or directions.

The industry of moving people between Mexico and the United States is serious, treacherous business.