There were citizens from four different countries inside.
Border Patrol agents at a Texas checkpoint found 60 people hiding in a refrigerated tractor-trailer on Saturday.
Agents assigned to the Falfurrias Border Patrol checkpoint sent a truck for secondary inspection that morning after a K-9 alerted officers to the trailer, according to the U.S. Customs and Border Protection.
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Authorities said that upon searching the trailer, which had been set to 49 degrees, they found 60 people inside.
"The doors of the trailer were secured with a padlock and the subjects had no means of escape,” a press release said.
Agents reportedly found citizens from Honduras, Guatemala, Mexico and El Salvador inside.
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The driver, a Guatemalan citizen, was arrested at the scene, authorities said.
"Criminal activity like this will also lead to serious consequences for truck drivers who engage in smuggling," Chief Patrol Agent Manuel Padilla Jr. said in a statement.
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