From Feb. 25 – when the program called "No Pass" was launched along just three miles near El Paso – until March 9, 62 immigrants were apprehended, compared with 189 in the same period the year before. That's a 78 percent decrease – and to the US border patrol a sign that their principal goal of prevention is working.
The program also operates under the name "Lockdown," in an area further west along New Mexico's border. Almost all of those caught in this zone have been prosecuted.
Albelardo Flores Rojo is one of the most recent. He was detained just outside El Paso. Had he crossed east of the No Pass zone, the Guadalajara native, who was on his way to meet relatives in Los Angeles, most likely would have been returned to Mexico within hours.
Instead, last week he was at the US border patrol's processing center, wearing a red bracelet to signify he will not be going home.
"I was scared, I had no idea I'd go to jail," says Mr. Flores Rojo.
In the past, immigrants who have attempted to cross repeatedly, and all of those with criminal records, were prosecuted. Now, there is no distinction between first-time crossers and those with criminal pasts. All will face charges.
The program has provoked a hailstorm of criticism.
"This is not going to stop immigration, it's only going to push them into more isolated areas," says Fernando Garcia, executive director of the Border Network for Human Rights in El Paso. "They will need more help from smugglers. It will only increase the number dying across the border."