"It's going to grow, and it's going to surprise a lot of people who were hoping we would go away," one Minuteman says.
They're not going away, CBS News correspondent Lee Cowan reports.
The Minutemen have been trying to expand beyond Arizona, to California, New Mexico and Texas. To prove their increased numbers, they launched what they call a 30-day patrol this month with thousands of volunteers turning out to guard the border in all four states.
"I think our next 9/11 is going to be coming right through this Southern border," Minuteman Dr. Lee Vickers says.
Vickers, a veterinarian and a rancher, is helping to lead the charge in Texas.
He estimates at least 100 illegal immigrants sneak across his ranch every single night. His duty as a Minuteman, he says, is simple: "To document this flood of people, to try to assist the border patrol to catch them and to show Washington what's going on andhow bad it really is," Vickers explains.
But this month, the Minutemen also tried another tack — not just patrolling the border, but
Chris Simcox is the organization's president.
"Our job is to intimidate law enforcement," Simcox, president of the Minutemen Civil Defense Corp, says.
But they're not targeting law enforcement. They're targeting day laborers — undocumented immigrants, who gather on street corners looking for work while the Minutemen say police look the other way.
"We want to go after the fact that people are employing illegal aliens and that's a violation of federal law," Simcox says.
They're now videotaping those doing the hiring and if it scares off day laborers like Jose Sedillo in the process, that's O.K. too.
One man told Cowan he would run if Minutemen appeared at his corner. "But I'm not doing anything wrong. I'm just looking for work," he says.
Critics argue it's not only unreasonable to expect the police do to the work of the immigration officers, but it's practically impossible.
"They don't have enough police officers to keep the city as safe as it needs to be, and putting them in charge of border enforcement would be a massive disaster," Rene Wizig-Barrios of the Industrial Areas Foundation, a non-partisan community political group, says.
Either way, Vickers isn't proud of trying to shame his government into fixing the problem, but as he puts it: "We have no other choice, we're on our own out here," he says.
Not a new frontier, but an old one, growing more crowded by the day.