"NOT FEASIBLE" TO CATCH EVERY TRUCK DANGEROUSLY PACKED WITH MIGRANTS, SAYS BORDER PATROL AT CHECKPOINT WHERE 10 MIGRANTS DIED IN AN 18-WHEELER SMUGGLING HUNDREDS, THIS SUNDAY ON "60 MINUTES"

No one knows how many trucks dangerously loaded with smuggled migrants are getting through checkpoints near the U.S.-Mexican border. At a screening area in Laredo, Texas, where one such 18-wheeler made it through packed with more than 100 migrants - 10 of whom later died - border officials tell Scott Pelley it's "not feasible" to catch all the trucks given the high traffic volumes they deal with. Pelley reports on a growing and dangerous method of smuggling migrants into the U.S. in a 60 MINUTES story to be broadcast Sunday, March 11 (7:00-8:00 PM, ET/PT) on the CBS Television Network.

"It's unfortunate, but the possibility of us catching every single thing to come through this checkpoint is just not feasible," says Jason Owens, the deputy chief at the Border Patrol checkpoint on Interstate 35 in Laredo. Owens says, "The agent... has just a couple seconds, given the amount of traffic that comes through and so... whenever they talked to the driver, didn't have that reasonable suspicion." The truck traveling to San Antonio sailed through the check point and traveled three hours with temperatures inside climbing to 120 degrees and leaving 10 dead and 29 critically ill.

The increase in the dangerous smuggling is due to more migrants fleeing increased gang and drug cartel violence south of the border, says Jeremy Slack, a professor at the University of Texas at El Paso who has been interviewing migrants for years. "Now not only do people have no economic sustenance, but they also have people trying to kill them," he tells Pelley.

Pelley speaks with a survivor of the deadly San Antonio truck, Jorge de Santos Aguilar, a 42-year-old Mexican laborer who can earn $5,000 a month in the U.S., but only about $300 a month in Mexico. "I heard a lot of screaming. They wanted water... there were some people saying they wanted to die," he remembers. "I heard a mom scream for her children. The last thing I remember was calling out to God," says de Santos.

Two of the 10 who died locked in the stifling trailer of the truck were children.

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