LAREDO - Freight and delivery service truck drivers on Thursday denounced as dangerous and unfair a pilot program allowing up to 100 Mexican trucking companies to transport their cargo anywhere in the United States.

Carrying signs reading “NAFTA Kills” and “Unsafe Mexican Trucks,” a few dozen protesters circled in the heat for two hours at a port of entry at the World Trade Bridge on the U.S.-Mexico border.

“What do we want? Safe highways. When do we want them? Now!” they chanted.

The U.S. Transportation Department was expected to begin issuing operating permits in the program as early as Thursday.

The Teamsters union, Sierra Club and nonprofit group Public Citizen sued to try to stop the program, arguing there won’t be enough oversight of the drivers entering the U.S. from Mexico.

But a federal appeals court ruled last week that the Bush administration could move ahead.

Government lawyers said the program was a necessary part of the North American Free Trade Agreement and the trucks enrolled in the program would meet U.S. regulations.

“There are no means to regulate these guys. Bush has opened up highways to unsafe trucks,” complained Teamsters organizer Hugo Flores. “I don’t want them sharing the roads with my family.”

Flores said the main concern is over the length of work shifts and drug testing.

“We’d have less concerns if they were working under the conditions we’re working under,” Flores said.

Oscar Rodriguez, who has driven 16 years for UPS, said he thinks law enforcement will be less vigilant about watching out for unsafe truckers the farther they travel into the country.

“As it is we do have incidents with American trucks,” said Rodriguez, of Laredo. “Who’s regulating the Mexican truck drivers? They could drive 16 hours, popping pills. We don’t know.”

Interstate 35, which stretches from the U.S.-Mexico border in Laredo north to Minnesota, is a major north-south artery though the country.

“Those guys run all the way here and all they way back without sleep,” said Roadway Express driver William Scribner, of Laredo. “They don’t respect the laws, they don’t respect the people.”

Scribner said he has seen drivers come across the border in two-seat cabs, then pick up two workers, meaning there aren’t enough seat belts for everyone.

NAFTA requires that all roads in the United States, Mexico and Canada be opened to carriers from all three countries. Canadian trucking companies already have full access to U.S. roads, but Mexican trucks can travel only about 20 miles inside the country at certain border crossings.

The current pilot program is designed to study whether opening the U.S.-Mexico border to all trucks could be done safely.

But even if that’s possible, Flores said there are still concerns about job security and pollution from emissions.

“Now they’re trying to export all our driving jobs to Mexico,” Flores said. “That’s one less American job.”

About a dozen Laredo police officers stood watch Thursday, but the Teamsters said they weren’t there to cause trouble. As trucks passed by, some honked in support, other drivers gave the group the thumbs up.

A Teamsters rally also was planned in San Diego Thursday.

At a Petro truck stop near El Paso along Interstate 10, reactions to the program were mixed.

Carlos Moreno, who has been a truck driver for nearly four decades, said he doesn’t begrudge anyone trying to make a living.

“There’s enough for all of us,” said Moreno, an El Paso resident.

But he is concerned that some of the drivers from Mexico won’t be able to read highway signs written in English.

“The only thing that scares me is that they can’t read,” Moreno said. “You can always tell in construction zones.”

Omar Nunez, a 34-year-old driver from Pecos, said he worries that freight prices will drop as shippers turn to Mexican trucking companies that may offer cheaper services.

“As it is, I’m barely making it right now,” he said.

Associated Press writer Alicia A. Caldwell contributed to this report from El Paso.