Border Patrol officers on March 14 arrested 29-year-old Jose Gustavo Diaz-Velasquez in Rio Grande City. A judge in McAllen on Wednesday ordered him held without bond on immigrant smuggling charges.
Investigators believe Diaz-Velasquez has been living illegally in the U.S. Further details on where he's from in Mexico were not immediately released.
The investigation began last August when federal agents identified at least 10 online postings believed connected to the human smuggling ring.
Officials traced the Craigslist postings to a McAllen apartment associated with the suspect's wife.