Laredo Sector Border Patrol agents rescued ten migrants from tractor-trailer rigs being towed through a South Texas immigration checkpoint.

Laredo North Station agents assigned to the Interstate 35 Immigration Checkpoint between Laredo and San Antonio rescued ten migrants who smugglers locked inside two 18-wheeler tractors being towed on July 23. Despite the heat of the Texas summer, the migrants did not require medical attention, according to information provided by Laredo Sector Border Patrol official.

The agents observed a white tractor pulling two additional tractors enter the primary inspection lane. During the initial interview, a K-9 agent responded to an odor it is trained to detect, officials stated. The agents referred the driver to a secondary inspection station.

During the subsequent search of the two towed tractors, the agents found five migrants packed into each cabin. The agents conducted a biometric background check on the migrants and determined them to be Mexican and Salvadoran nationals who had entered the U.S. illegally from Mexico.

The agents provided an initial medical evaluation of the migrants and determined that none were in need of medical attention. They placed the ten individuals into custody and processed them for immigration violations, officials reported.

Agents determined the driver of the rig to be a U.S. citizen and placed him under arrest for possible charges related to human smuggling. Officials seized all three of the tractors.

Laredo Sector agents frequently find migrants being smuggled in tractor-trailers and other cargo trucks placing the migrants lives in danger from heat-related illness or injury in the event of a crash.

In May, a Laredo Sector K-9 alerted to another tractor-trailer at this same checkpoint, Breitbart News reported. An inspection of the trailer yielded 66 migrants who were locked inside with no means of escape in the event of a crash or abandonment by the human smugglers. Agents said the 66 migrants included two juveniles.

“The Laredo Sector Border Patrol will continue to warn against the dangers of people crossing illegally into the United States through dangerous environmental conditions,” Laredo Sector officials said in a written statement at the time. “Our Border Safety Initiative (BSI) is a humanitarian, bi-national strategy designed to reduce illegal alien deaths, educate and inform potential illegal aliens of the dangers and hazards of crossing the border illegally, and to respond to those who are in life-threatening situations.”