POSTED: 09:57 AM MDT Jul 16, 2016

U.S. Border Patrol agents have rescued 11 immigrants in South Texas who were being smuggled in a closed refrigerated trailer.

Officials announced the rescue took place Friday morning at a checkpoint in Falfurrias.

Officials say the tractor-trailer rig's driver became visibly nervous while being questioned and was sent for secondary inspection.

During the inspection, agents discovered the immigrants hidden in the trailer's cargo area.

The immigrants included nine Mexican citizens, one person from El Salvador and one person from Honduras.

The driver, a U.S. citizen whose name was not released, was arrested. Authorities did not immediately provide additional information on charges against the driver.