The U.S. government plans to fly nearly 34,000 illegal Mexicans back to their country this summer as part of a $14.2 million program aimed at stemming human smuggling, border officials said on Wednesday.

The program, which has been criticized by rights groups who say it is expensive and does little to stop the flow of illegal immigrants, will enter its second year when twice-a-day flights begin from southern Arizona on Friday.

Customs and Border Protection Commissioner Robert Bonner said the program aims to reduce the number of illegal migrants who die crossing each year — particularly during the summer, known as the “season of death.”

“In a post 9/11 era, in an era in which al Qaeda itself has contemplated using the Mexican border to move terrorist operatives into the United States, it’s absolutely essential that we do this. This is what helps us control the border,” Bonner told reporters.

“We also … need to do this as well to reduce the number of people that die each year in the desert, particularly in the very hot summer season in Arizona.”

Customs officials said at least 160 people have died so far in fiscal 2005 trying to cross the border.

Mexicans who decide to participate in the program will be flown to Mexico City then sent by bus to their hometowns.

The controversial program to ship illegal Mexicans to their hometowns rather than simply dropping them off on the Mexican side of the border was a touchy issue for Mexicans sensitive to U.S. interference in their internal affairs.

But both countries agreed on the need to boost security on the 2,000-mile border to reduce the number of deaths.

Bonner rejected criticism that the program was ineffective and said the goal was to ship the Mexicans away from the border where they might fall prey to the same smugglers who tried to get them across the first time.

“It’s more than a Band-Aid,” he said. “One of the important things of this will be that we are able to repatriate to the interior of Mexico. If we do that, we will meaningfully reduce the number of people that are coming back the next day.”

Customs officials said they could repatriate a total of 33,900 migrants on twice-daily flights from Tucson to Mexico City through the end of September.

The program is expected to cost about $14.2 million this year, down from about $15.4 million last year when about 14,000 Mexicans were flown back to their country.