U.S. Border Patrol agents stopped a pickup truck towing a utility trailer Tuesday morning and got more than they bargained for.

The pickup was driven by a 31-year old man , a Mexican national , who was seen driving away from a location known for human and narcotic smuggling. The driver told agents that there were people in the trailer. The trailer , 12 feet by 6 feet , was crammed with 38 people , two of them juveniles. The trailer was locked from the outside and the people were without food , water , ventilation or safety restraints. Four other undocumented immigrants were found in the truck. The driver was placed under arrest. The incident remains under investigation.