A Kansas man was arrested Thursday at the Falfurrias Border Patrol checkpoint after 24 undocumented migrants were found in a trailer he was driving, according to a criminal complaint.

Among the migrants who were found was a 4-year-old boy, the complaint stated.

Robert Monkel was arrested on federal human smuggling charges in connection with the incident, court records show. 

According to the complaint, Monkel was the driver of a refrigerated tractor truck and trailer that arrived at the Border Patrol checkpoint in Falfurrias on Thursday, Nov. 7 at 5:30 a.m.

During a search, Border Patrol agents found the migrants hidden inside the refrigerated trailer on top of pallets of produce, the complaint added.

Agents observed that the reefer temperature was set at 35 degrees Fahrenheit.

Monkel and the 24 migrants were detained, and a handgun and ammunition were found inside a bag in the tractor-truck, the release added.

One of the migrants provided a statement to authorities and said he had made arrangements with a smuggler to be taken to Houston for $18,000. 

Monkel is expected to make his initial court appearance on Tuesday morning in Corpus Christi, court records show.