Border Patrol agents in Arizona found nine immigrants locked inside the cargo area of a U-Haul, AzFamily.com reports.
Agent searched the trucks after becoming suspicious of the driver and passenger at a checkpoint near Amado.
Inside were eight adults and one juvenile who had no fresh air or ability to escape.
An undocumented immigrant was killed a similar way last summer.
“Transporting people inside the cargo area of a vehicle is extremely dangerous due to heat, the possibility of a vehicle accident, or other unforeseen circumstances,” the agency said in a statement.